Overall, I don't have an issue with bounded accuracy. But I do like adding in more skill challenges (a concept from 4e that I find carry over quite well) where you need to obtain a certain number of successes before a certain number of failures to solve/progress certain situations. Incentives can be given for collaboration in such situations. 

Granted it is not as fast as a straight forward ability check (with or without proficiency), but it creates some fun situations and opportunities for collaboration. It's not a mechanism that is directly associated with bounded accuracy, but needing multiple successes  to achieve outcomes does play with the math since the single roll doesn't define the entire outcome. I find that I prefer this mechanism slightly over 5e group skill checks, but that's just my preference. 

I think my only other aspect that is related to bounded accuracy is the downplaying of magical items in their role to help/boost characters. The largest amount of modifiers now stem directly from the characters, and less from items. That is good in some ways since it opens up for low magic campaign styles to not flounder, but perhaps slightly dampens the excitement of new loot :)

It limit modifiers and target numbers by keeping them more closely bounded, resulting in lows and highs remaining more relevant and a greater impact from d20. Low power creatures can remain a threat or significance across levels because they can still hit high DC or AC and powerful ones can miss just as well.

Quote from IamSposta >>

In almost 30 years of playing across several editions  I have never found the math of D&D very challenging, personally speaking. However, many of my friends found it too mathy for their tastes. To me, the biggest advantage of bounded accuracy (among other things) is that 5e is the first edition of the game many of my friends don’t hate, so I get to play more D&D now.

 The only reason I'm playing 5th is that my friends don't want anything more complicated. Otherwise, I wouldn't be playing 5th. I miss 2nd. Not the system, but the sheer amount of lore and world building. To me, bounded accuracy is an abomination. The difference in hitting between melee and non melee characters is much, much too small.

I will say that I'm strongly tempted to eliminate bonus dice (replace the roll with a flat value) and non-stacking (you can only apply one to a roll). Then go through and take every '+5' bonus and change it to 'advantage'.

Quote from Baron_Von_Cart >>

I have a huge huge problem with Expertise. I love it when playing a Rogue, hate it as a DM.

Pretty sure the game would be better by saying Proficiency starts at 0, and will cap at 4. Also, Expertise gives you the Prof Bous/2, rounded up.  I need to run through the various combinations and permutations of such changes.

 Why start proficiency at 0? Would be kind of lame to start the game with proficiency not meaning anything for the first few levels. 

I can see having an issue with expertise, especially at later levels where it scales really high. starting off with a prof bonus of 0 is baffling to me. I don't really feel like the current 2 to 6 format is busted or anything, it's only really things like the rogue exertise/reliable talent combo that can get crazy. 

Quote from Erokow32 >>

 

3) Giving bonuses diminishing returns, thus insentivising creativity?

 Just to play Devil's Advocate as someone who got a tiny dopamine rush for every fiddly 4e bonus I could stack, removing those does not necessarily incentivize creativity. There are min-maxers who want to break the game, and then there are min-maxers who use their "powers" to make weird builds that totally wouldn't otherwise work and use all those bonuses just to bring them up to parity with a "normal" build.

Our ability to do that in 5e is quite limited, as evidenced by the sheer amount of terrible multiclass combinations or even just out-of-the-box subclasses that that perform objectively worse than the other options available. In a more flexible system, some of those stinkers would be salvageable. If you want to make a highly unorthodox build outside of a few clever combos, you have no choice but to be a burden on your party members and just overall less successful as an adventurer. Doesn't sound like incentivizing creativity to me, or rather by limiting your mechanical creativity, they force you to strive harder to distinguish yourself through roleplay. I can understand some seeing that as a desirable feature rather than a flaw.

Not that I hate bounded accuracy. I mean I am here, playing this system instead of others. It certainly makes monsters applicable over a wider range of levels (which would be a lot more useful if 5e had good monsters to use). And certainly as a DM I have less worries about handing out enough gear to have everyone's bonuses about where the game expects them to be.

As for moving the goalposts when it comes to skill DCs, I'm not afraid to let PCs be good at the stuff they want to be good at. Does Eloquence Bard trivialize social encounters? Sure it does. Good thing the game provides more ways to challenge a party than just social encounters. Same thing for stealth checks or deception or whatever. No one is good at everything, so let them have their wins and then challenge them with stuff they haven't chosen to be good at. That's when the creative solutions come out, and winning because you figured a way around your weakness is more fun than winning because you managed to roll high.

So, we have the game designer's own words for what bounded accuracy is for (you have to find archived copies, but various people have noted them down). I think BA actually fails many of the stated objectives but has still had some possibly useful side effects. Some points:

The basic premise behind the bounded accuracy system is simple: we make no assumptions on the DM's side of the game that the player's attack and spell accuracy, or their defenses, increase as a result of gaining levels.

This is... objectively not true in 5e. Higher level characters have higher attack and spell DC, higher level monsters have higher attack and AC. What they actually did was slow down the progression.

This extends beyond simple attacks and damage. We also make the same assumptions about character ability modifiers and skill bonuses. Thus, our expected DCs do not scale automatically with level, and instead a DC is left to represent the fixed value of the difficulty of some task, not the difficulty of the task relative to level.

This is an error in representing previous editions. DCs in every edition reflect the difficulty of the task, previous editions have just assumed higher level PCs are running into more difficult tasks.

Getting better at something means actually getting better at something. Since target numbers (DCs for checks, AC, and so on) and monster accuracy don't scale with level, gaining a +1 bonus means you are actually 5% better at succeeding at that task, not simply hitting some basic competence level.

They don't scale with the PC level, but they never did. They scale with the enemy level, just like they did in every edition (good luck making a DC 26 check to sneak up on an ancient red dragon with your first level rogue), just slower (that 26 is only 12 points higher than a red dragon wyrmling, whereas in 3.5e you were looking at 34 points difference).

Nonspecialized characters can more easily participate in many scenes. While it's true that increases in accuracy are real and tangible, it also means that characters can achieve a basic level of competence just through how players assign their ability bonuses. Although a character who gains a +6 bonus to checks made to hide might do so with incredible ease, the character with only a naked ability bonus still has a chance to participate. We want to use the system to make it so that specialized characters find tasks increasingly trivial, while other characters can still make attempts without feeling they are wasting their time.

I believe this is the most important idea behind BA. And, well, it fails at high levels. At first level, the difference between best-in-party and worst is generally not more than 8 points (8 stat vs 16 stat+expertise) and usually lower (in 3.5 that was about 9, in 4e about 10), which achieves the goal. At max level, the difference between best-in-party and worst is probably 18+ points, which doesn't (3.5e could easily have 40+ point swings, 4e maxed in the low 20s).

The DM's monster roster expands, never contracts. Although low-level characters probably don't stack up well against higher-level monsters, thanks to the high hit points and high damage numbers of those monsters, as the characters gain levels, the lower-level monsters continue to be useful to the DM, just in greater numbers.

In practice, low CR monsters are unusable at high levels, though the range of viability is larger than in previous editions.

Bounded accuracy makes it easier to DM and easier to adjudicate improvised scenes. After a short period of DMing, DMs should gain a clear sense of how to assign DCs to various tasks. If the DM knows that for most characters a DC of 15 is a mildly difficult check, then the DM starts to associate DC values with in-world difficulties. Thus, when it comes time to improvise, a link has been created between the difficulty of the challenge in the world (balancing as you run across this rickety bridge is pretty tough due to the breaking planks, especially if you're not a nimble character) and the target number. Since those target numbers don't change, the longer a DM runs his or her game, the easier it is going to be to set quick target numbers, improvise monster attack bonuses and AC, or determine just what kind of bonus a skilled NPC has to a particular check. The DM's understanding of how difficult tasks are ceases to be a moving target under a bounded accuracy system.

Again, this is either misunderstanding prior editions, or just wrong. Does 'mildly difficult' mean 'mildly difficult for the PCs' or 'mildly difficult for some standardized character'? In the first case, it varies with the PCs abilities, just like prior editions. In the second case, it's invariant in all editions.

It opens up new possibilities of encounter and adventure design. A 1st-level character might not fight the black dragon plaguing the town in a face-to-face fight and expect to survive. But if they rally the town to their side, outfit the guards with bows and arrows, and whittle the dragon down with dozens of attacks instead of only four or five, the possibilities grow.

This is true but not obviously desirable. What if you want an unstoppable monster that needs a band of heroes to deal with, instead of having the town guard kill it?

It is easier for players and DMs to understand the relative strength and difficulty of things. Under the bounded accuracy system, a DM can describe a hobgoblin wearing chainmail, and, no matter what the level of the characters, a player can reasonably guess that the hobgoblin's AC is around 15; the description of the world matches up to mechanical expectations, and eventually players will see chainmail, or leather armor, or plate mail in game and have an instinctive response to how tough things are.

How does this differ from 3.5e? 4th edition did make higher level creatures harder to hit, but "a more skilled fighter is harder to hit" doesn't seem peculiar.

It's good for verisimilitude. The bounded accuracy system lets us perpetually associate difficulty numbers with certain tasks based on what they are in the world, without the need to constantly escalate the story behind those tasks. For example, we can say that breaking down an iron-banded wooden door is a DC 17 check, and that can live in the game no matter what level the players are. There's no need to constantly escalate the in-world descriptions to match a growing DC; an iron-banded door is just as tough to break down at 20th level as it was at 1st, and it might still be a challenge for a party consisting of heroes without great Strength scores. There's no need to make it a solid adamantine door encrusted with ancient runes just to make it a moderate challenge for the high-level characters.

It isn't? News to me. Also, why is it bad that a level 20 character can casually blow through an iron-banded wooden door?

Anyway, of these goals, by far the highest value is reducing the swing between best-in-party and average, and if want to keep that true at high levels, you have to either make it so the specialists can't improve, or make it so everyone improves.

Quote from Pantagruel666 >>

Also, why is it bad that a level 20 character can casually blow through an iron-banded wooden door?

Well, you're dismissing the point, but the idea that a character can do that is what is bad for verisimilitude.

You're correct that they just slowed down the way characters power up over level, ultimately reducing the gap between the lowest and highest levels. One reason is that that gap defies belief, to some people.

Quote from kenclary >>

Quote from Pantagruel666 >>

Also, why is it bad that a level 20 character can casually blow through an iron-banded wooden door?

Well, you're dismissing the point, but the idea that a character can do that is what is bad for verisimilitude.

You're correct that they just slowed down the way characters power up over level, ultimately reducing the gap between the lowest and highest levels. One reason is that that gap defies belief, to some people.

 So a 20th level fighter can beat up a 24' tall cloud giant but is stymied by a wooden door? If you don't want PCs doing unbelievable things, don't let them get to high level.

Quote from Pantagruel666 >>

Quote from kenclary >>

Quote from Pantagruel666 >>

Also, why is it bad that a level 20 character can casually blow through an iron-banded wooden door?

Well, you're dismissing the point, but the idea that a character can do that is what is bad for verisimilitude.

You're correct that they just slowed down the way characters power up over level, ultimately reducing the gap between the lowest and highest levels. One reason is that that gap defies belief, to some people.

 So a 20th level fighter can beat up a 24' tall cloud giant but is stymied by a wooden door? If you don't want PCs doing unbelievable things, don't let them get to high level.

That's, like, exactly what bounded accuracy is about. The difference between what a level 1 character can do and what a level 20 character can do is made smaller.

Sure, you could just fix the problem by capping everyone's level to level 6 or something. (Wasn't there a 3.5 option / houserule to do just that, and just replace further levels with feats?) Bounded Accuracy makes the game better by reducing the need.

Quote from kenclary >>

That's, like, exactly what bounded accuracy is about. The difference between what a level 1 character can do and what a level 20 character can do is made smaller.

At first level, a DM might block an entrance with a couple goblins, or with an iron-bound wooden door.

At 20th level, the PCs are going to casually blow through a couple of goblins, so either the DM decides that this entrance is not a challenge, or upgrades the guards. Why should it be different for doors?

 Just so everyone is on the same page, here is the full archived article on Bounded Accuracy that Pantagruel was quoting from, so you have more to go on than just the quoted portions.

Quote from Farling >>

Bounded Accuracy means that all PCs have a chance to succeed.

There is less reason to min-max when the difference is a lot less than in earlier editions.

 Yup, in 5e, even a person with a negative ability modifier can succeed if they roll high enough.

I like how it makes it less restrictive on what certain characters can do, just because of their modifiers.

Also, it always makes the job easier to have lower numbers.