Do y'all pretend not to notice when the DM fudges something to keep your character alive?
Sometimes I can tell when my current DM fudges a roll to miss an attack or reduce damage. He has a tell in the specific way he pauses and breathes before announcing the roll, then tries to hurry to the next turn, which only seems to happen when someone is in a life-or-death scenario, but "luckily" survives.
Should I let him know he has a tell? Will it be less fun (or more stressful) for him if he knows I know?
I'm still a pretty new player, but I'm fairly certain that in my group's second combat encounter, our DM saw that we were going to struggle, so a few rounds before he thought we'd die, he started hinting that people on the street were hearing us. He didn't play around with his rolls at all, which meant us getting hit by some very powerful (even permanently crippling) critical hits, and some of us rolling awfully on his critical miss table. As we started to go down, one by one, the door was getting battered, and when the crew was down to 1 member alive, the city guard arrived and intervened, scaring the remaining mobs and healing up the three of us on the floor.
To me, it meant that he cared about the dice rolls and wanted consequences and actions to feel real, but also he didn't want our journey to end on the first night. But he didn't make the entire encounter feel like a victory, and our characters had to deal with the repercussions of that encounter.
Sometimes that's what it takes for new players to really feel and understand the consequences of their actions. Combat might not always be the best solution and escaping a battle is always on the table.