Battlefield Uncertainty: Combat applies -5/disadvantage to Passive scores

OK. I've simplified it to 2 basic rule changes, plus 2 changes that apply to martial classes only.

(1) During combat, if you take the Search action or bonus action on your turn, for a Perception check, whatever you roll+modifiers results in, that result becomes your passive perception score until the start of your next turn. 

(2) During combat,  if you do NOT take the Search action on your turn, your Passive Perception is 10+modifiers with a -5/disadvantage penalty for Battlefield Uncertainty until the start of your next turn. (note: this disadvantage cancels any advantage from things like Sentinel Shield to your passive perception score)

(3) Barbarians, Fighters, Monks, Rangers, Rogues: at level 5, these classes can Search as a Bonus Action. (i.e. to avoid the Battlefield Uncertainty penalty, use bonus action to Search)

(4) Barbarians, Fighters, Monks, Rangers, Rogues: at level 10 these classes do not suffer the Battlefield Uncertainty penalty (no -5/disadvantage). (i.e. Sentinel Shield advantage is no longer canceled by battlefield uncertainty disadvantage, so Sentinel Shield applies +5(advantage) to passive perception).

Having spent a lifetime training in the art of war, martial classes are eventually able to overcome the Battlefield Uncertainty penalty.

Note: All active rolls for perception, etc, are unaffected by Battlefield Uncertainty. 

I'd say concentration on a spell is a flat -5 (not disadvantage, just -5) penalty to perception (both active and passive), but that's another conversation

What is the benefit of this?

Your passive percpetion is 10+mods. which is the average result of an active perception check.

when you are taking the attack action, your passive percption is 10+mods. When you are juggling 6 handgrenades, its 10+mods. When you do nothing, its 10+mods. When you stare into the void, its 10+mods.  When you focus every fiber of yoru being into searching, its 10+mods.

In the middle of combat, if you're not actually taking the Search Action, your perception shouldn't be as good, on average, as if you HAD taken the Search action.

Not to mention that if you take the Search Action and roll a perception check, half the time, you will roll worse than your passive percption, so you're probably better off doing nothing and relying on your passive perception score which never waivers.  Which is why basically no one takes the Search action during combat. Passive is reliably good.

These rules attempt to fix the above issues, without making things too complicated.  Basically, its adding a possible disadvantage penalty, which is the simplest solution I could come up with. And adding a feature to martial classes that reflect builds that overcome this penalty.

Quote from Maruntoryx >>

What is the benefit of this?

 Looks like the main idea is to just bring a bit of realism into the game. Although I would a rogue would get rid of the Uncertainty before level 10 as they get Reliable Talent at level 7 and whole "thing" of rogues is to be perceptive to exploit opportunities.

But as to a benefit, this would also make it easier for a creature to take the Hide action (did 5.5e use a flat DC for hilding instead of opponent's passive perception? I'm playing 5e so I don't remember by heart).

Quote from Scruvy >>

(did 5.5e use a flat DC for hilding instead of opponent's passive perception? I'm playing 5e so I don't remember by heart).

5.5 rules say to Hide you roll Stealth check DC 15.

But it also says you are hidden until a creature finds you, which some take to mean the dc of your stealth check is 15 or passive perceptiin of enemy, whichever is highest