To me this looks like you swung between two extremes - too much specificity and not enough. I suggest a reasonable standard of specificity, that is, enough where the DM doesn't have to assume what the characters are actually doing, but not so much that the game is bogged down.
What is reasonable exactly? One person's reasonable is another's way too specific.
It will be found if the PC is engaged in that task. Passive Perception doesn't capture everything all the time - just those tasks with an uncertain outcome where a passive Perception check would apply. If they are not engaged in that task, then passive Perception isn't used to resolve any uncertainty as to the outcome of said task. The trick is to make those tasks be legit trade-offs. "You can do X, but you can't also do Y at the same time which could mean Z." One task at a time, generally speaking (unless you're a ranger in favored terrain).
So, you're saying if I walk into a room, there is a secret door on the wall. There is a visible sign that door exists (Faded bricks, scratches on the floor from when the door opens, a seam around the door that is slightly unnatural) and I look at the wall (because my eyes aren't closed, so the light reflecting off those things is entering them) I have a 0 percent chance of seeing them until I say "I'm searching the wall"?
Are you saying that if someone comes walking up behind me that I'm incapable of hearing footsteps because I didn't say "I'm listening for people sneaking up on me?"
No, the rules you are referring to are still located in the section talking about using the metagame rules for using hour or day long exploration turns. They are very metagamey because they summarize the activity you take in an entire day.
When running in normal time, people's eyes and ears continue to work even while they are engaged in other activities. They just only work at a minimum level. That's what PP is. The minimum level of your senses when you aren't purposefully using them.
When you purposefully use them (make a roll), you can possibly roll higher than your PP and see things you missed when you weren't looking. But not looking doesn't make you blind.
Otherwise, the game would end up like this: "You walk into the room, there is a table. It is empty." "I search the table to see if there's anything hidden." "You see an apple." "Wait, there's an apple, just sitting on the table? I thought you said it was empty." "Yeah, the Perception check required to see it was 3. You don't get your Passive Perception while you are doing anything else, so you missed it."
I don't really see the upside to this approach. More process for what gain?
The upside of this approach is that with the DM rolling, the DM can use PP all of the time and doesn't have to listen to and process 6 people yelling out "I search the hallway, I got 15" "I got 17!" constantly, which wastes time while also avoiding the problem of a set DCs: If the game uses a "standard trap" stat block, it ends up with every pit trap in a hallway at the exact same DC. Which means if you have someone who has a PP of 15, they will spot every trap of DC 12 without ever searching 100% of the time. If you roll for each trap, then there's a chance the character spots 3 traps but misses the 4th one because it was slightly better hidden or the character was slightly more distracted.
First, players don't get to choose to make checks. They can only describe what they want to do. The DM takes it from there, narrating the results. Sometimes the DM is uncertain as to the result, so a check is required. Whether that's a passive check or a regular ability check (notice I don't say "active check" or "active roll" because that is misleading) depends on whether it's a task the PC is performing repetitively or "in general" while traveling the adventure location.
True, but some actions directly imply rolls. If someone says "I search the bottom of the desk drawer to see if there is a hidden compartment there." then they would like to make a roll to search since there's a chance that even though they searched the right place, the compartment might be too well hidden to be found.
If they have a PP of 14 and the DC is 15, casually opening the drawer and looking inside wouldn't spot it. However, if they choose to search the drawer, they could roll higher than 14 and therefore find the compartment. If they roll lower, they still don't find it.
I agree with the idea that people shouldn't be rolling unless the DM tells them to, but there are situations where players EXPECT the DM to tell them to so they just pick up dice and roll. I'm not sure what you suggest if someone says "I search the bottom of the drawer" and you say "Alright, roll a Perception check" and they roll 3 and you say "Sorry, you don't see anything." and they say "Alright, I search it again, since I'm convinced there's a compartment here. That note we found hinted at one."
Either you let them roll again, you declare they find it immediately, or you refuse to let them roll again and say they can never find it. There's only 3 choices. If you let them roll again, they can just keep repeating "I search again" until they get a 20. If you don't let them roll again, they get annoyed that you are denying them the right to search again. If you declare they find it immediately, then why did you bother with a DC in the first place? Just abandon the idea of Perception checks and rely on people telling you where they are searching.
So that deals with the issue of players rolling repeatedly "until they roll a natural 20."
So if the players say something reasonably specific along the lines of "We exhaustively toss this room floor to ceiling for anything notable, poking around every nook and cranny, taking whatever time we need to be thorough..." then you just tell them what they find without a check, passive or otherwise.
I used to allowed this back when I ran 2e and there was no such thing as Perception checks. But then every room became "We exhaustively toss the room, floor to ceiling..." to the point where "We search the room" became short hand for a long sentence describing that they search everything from top to bottom.
And running a game where each room was the exact same procedure was kind of boring: "You search the room. You find 20 gp glued to the bottom of the desk. You find a magic sword in a secret compartment under the bed. You find a key behind the mirror. Someone is writing this all down, right?"
Nothing was ever missed because if I tried to say "Sorry, I don't think 'I search the room' means you cut into the mattress. That's something beyond search the room." then the response was "Alright, so, you want us to be more specific then. Does that mean we have to say 'We exhaustively toss this room floor to ceiling for anything notable, poking around every nook and cranny, cutting into anything that could be used to hide something, taking whatever time we need to be thorough..."' every time we go into a room then? It's a mouthful, but if we have to repeat all of those words each time in order to make sure we get all the treasure, we will."
I opted for "I search the room" being good enough.
But after I started playing 3e and since then, I've kind of liked the idea that just searching in a place doesn't immediately find something hidden. That one person can be better at searching than another and might see something that someone else missed. I like the idea that luck factors into finding hidden things. That's what the Perception skill is for. So, when someone says "I search the wall for secret doors", I like the idea that the door might just be too well hidden to find, even if they are searching in the right place. But it might not have been too well hidden if they had a higher Perception.
So, by building a character with a higher Perception, they get real in game benefits for it. I can run the same adventure for one group and they can find the passage and get the extra treasure. I can run it for a different group and they'll m
So that shows an example of reasonable specificity obviating the necessity to go to the mechanics to resolve the action.
The issue with just letting the roll determine what the PCs actually did as you suggest is that this is in my view the DM overstepping his or her role in the game by establishing what the characters are doing rather than simply narrating the results of what the players say they try to do. You can run into a lot of problems by doing this if the players aren't onboard with what the DM establishes their characters as doing (that usually comes up when something bad happens e.g. "I didn't say I looked under the bed!").
The DM always uses the dice to determine what the characters actually do.
When you say "I hit the enemy with my sword" your roll determines if you succeed or not. If you roll well, you might have hit hard enough to pierce armor or you might have been adept enough to get around someone's guard. If you rolled poorly your attack might have been too weak or deflected. But the exact, detailed, action you took was determined by the dice. "I attack with my sword" can be completed in about 100 different ways. The dice determined how you completed it.
The same thing happens with "I search the room". You might search half-heartedly, just take a quick glance around and look in only the obvious places. You might spend the next hour searching everything.
If you specify you are spending the next hour searching everything, you might forget to look under the rug.
Yes, sometimes this means a player will say "I didn't want to search THERE!" and I'll say "Sorry, you said you search the whole room, that includes there." but if that happens from time to time instead of having to play 20 questions "Is it under...the rug?", it makes the game run a lot smoother.
People can specify they are searching differently. They can say "We search...but we don't touch anything" and I'm ok with that.