Really it just looks like you're talking about a preference and adding embellishment here. That there is a hallway is sufficient to state a goal and approach for the players. It's boring, sure, and more detail is better in my view, too. Still, the players can have their characters do stuff even with that little context and the DM can narrate the result of those actions, then repeat the play loop. Perhaps as a result of the PCs' actions, the basic scope of options has changed and there's now revealed environment for the DM to describe.
Of course. Giving a full description just bypasses some obvious questions, is all.
It has little to do with the DM's desire to have the players take any particular course of action.
Sorry, I don't buy this - assuming the players are paying attention and know your 'tells' (which inevitably becomes the case after playing with a given DM for any length of time) you're outright telling them "here's where the interesting stuff is".
It perhaps gives the DM the satisfaction of knowing that he or she runs a fair game without "gotchas"
Here's a huge preference divide between us, I think, in that I don't see "gotchas" as unfair in the least. Sometimes you'll see it coming, sometimes you won't, and most of the time there's a chance of one or the other depending on some dice rolling and greatly influenced by stated approach.
that encourages players to pay attention to gain a better chance of success. It potentially removes the impetus for standard operating procedures which by virtue of their rote nature can be a little stale. To some degree it forces the DM to be more descriptive, hopefully without becoming ponderous, which lends itself to a more immersive experience.
Encouraging players to pay attention and DMs to be more dexscriptive - always a good thing!
Nothing wrong with SOPs, though - far better than having to go through the whole process every time, and it's only realistic that adventurers, having once been exposed to hidden dangers, are always going to be on the lookout for such.
The DM decides what is obvious and what is not obvious. There is nothing that is by default not obvious. And telegraphing isn't making anything obvious - it's just a clue in the environment. The blood stain on the wall opposite the door. An acrid smell in the air of an otherwise empty chamber. A hollow sound when traversing the stone floor. These things invite exploration rather than obviate it.
There are many things that are by default not obvious. Secret doors are one. Motivations and rationales behind NPC (or even PC) actions can be another. Hidden traps are another. Need I go on?
And while those telegraphing clues you give do invite further investigation of those particular areas, the flip side is that the areas without those clues aren't getting the same attention - which realistically they should be.
If the players investigate, perhaps they find a trap or perhaps they fail to do so. Or maybe they don't investigate - it's up to them, after all - and they run afoul of the trap that you telegraphed. When they then think about the clues you provided, they know they could have avoided their fate but didn't, for which they can only blame themselves rather than the DM for hitting the party with "gotchas." Oh, that explains the blood stain on the wall - argh!
True, and sometimes this is great! But not every time.
Sometimes there's going to be the deadly trap that has no clue provided as to its existence. Sometimes there's going to be the NPC who lies through his teeth and give the PCs no reason to suspect anything. Sometimes there's going to be the secret door that if left unfound means the whole mission is a failure, and they don't find it. These things would happen now and then in reality, so why not in the game?
