*facepalm*
This has gotten so far off topic it's ridiculous. It started from a tangential remark about how a character in heavy armor might still sometimes need a decent dexterity.
If you have a hallway with a hidden pit trap or "bottomless" pit or pit of lava, which were your own examples, and the adventurers MUST walk down that hallway in order to complete their mission-- that is a planned event. Like it or not, the moment you put that there you have planned to have the party do a save or die.
Who said it was hidden? I explicitly said I don't use save or die traps placed to catch unwary characters. That seems to be your hangup.
I'll give you an example, though I doubt you'll read it as you seem determined to misunderstand what I am saying. In a recent game I had a bottomless pit in the center of a dungeon room. On the opposite side was a golden statue with one arm palm upturned pointing at the party. Water ran forcefully from knee-high gratings around the edge and into the pit. Crossing recklessly would involve walking through rushing knee-high water on a slick stone ledge. Yes, that is a DEX save or die situation. Did I railroad the players into it? No. There were multiple ways to avoid the save. First, I knew there was a spellcaster with levitate. They could have crossed and tied a rope off allowing everyone to make the crossing without a save. They could also have found the hidden lever (on their side) which closes the grates and shuts off the supply of water. Finally they could devise a way to put a weight into the statue's hand, or merely pull it downward, either directly or with a thrown and weighted rope if they couldn't figure out a way across. As it turns out, the sorcerer in the group considered spider climb before using misty step (two alternatives I hadn't even considered) and pulled the statue's arm. Pulling the statue's arm closed a grating above the pit, allowing the water to flow harmlessly.
That is how it is done.
Sure, you could come up with some rationalization like "well, you should do a search check every single time you take a 5' step and poke everything tile you might step on with a 10' pole before taking a step or it is totally your fault because YOU put yourself in that situation!!" If you spend more time rolling search checks than you do anything else, you really have drained all enjoyment out of the game.
And let's say they do start doing that to pleasure you. "HA!! Spikes come out from the ceiling down on you! Save or die!! You said you were checking the floor. Its your own damn fault for putting yourself in this situation where you weren't checking the ceiling."
Sounds like you've had a bad DM at some point.
When the check the "walls" you make them specify left or right and if they choose the right wall, lava spurts out from the left one! Save or die!!
No, you put that damn pit there intending to make everyone roll a Dex save or die, you have planned to have one party member die. Just because they can't mind read you and know the action you predetermined was the right one to "avoid" the situation chose one of the other dozen possible actions is not "putting themselves in the situation". You are the one who put them there.
A really bad DM.
Same deal if they need to fight a golem or other large creature that cannot by pushed but can easily push them on a narrow bridge above such an "autodeath" area and the only way around this scenario is to give up on the mission that you NPC assigned them, go home and retire from adventuring. Saying "well, if they go ahead with this it is their own damn fault" doesn't fly-- YOU are the one who chose to set up the scenario in precisely such a way that you mathematically more or less guaranteed that at least one party member was going into that lava. You solely made the choice that the room would be shaped in that way and have that particular hazard combined with that particular enemy.
That is a planned event. You might not call it "railroading" simply because you gave them the option to quit and go home and let the town turn into zombies or let the dragon cult win, but it really is no better.
Good lord. A horrible DM.
Or worse, I am willing to bet you are the kind of person who if the players do a search check on a door and roll high, there is never a trap. But the one time they don't roll a search check or roll low, that's the time you are going to claim there is a save or die poison dart trap and if you get tired of them checking every door, then in the next one there is a small bug inside that will leap into their eyeball and burrow its way into their brain killing them if they fail their save.
Those are planned events and claiming that players are putting themselves in those situations and saying it is their fault is just bad rationalizing for your own actions.
Now you're just being insulting. I imagine you are one of these kinds of players:
DM: You stand before a small lake of bubbling lava. You can see a small island of rock about thirty feet from shore with a large glittering ruby floating above it.
You: I run across the lava and grab the gem.
DM: You are dead.
You: What? Why?!
DM: Dude, you deliberately stepped...no...ran
into lava.
You: But look how many hitpoints I have!
DM: Not any more.
You: What about my armor?!
DM: Why do you think that would make any difference at all?
You: You didn't even let me make a save! You're being unfair!
DM: Saves are for when you are trying to avoid something. You ran headlong into a lake of lava
on purpose.
You: But...
DM: You are dead. What is everyone else doing?
Party (in unison): Not running into the lava!
