You'll hear folks say old school gaming isn't all about fighting it's about exploration. And that's true... except of course the vast amount of the game rules support fighting and avoiding fights you can't win.
Sure there are rules for exploration and the descriptive exploration method works fine but...when was the last time someone in your game tried to get a monster drunk? Challenged an orc to an arm-wrestling match? Just plain-out bribed a monster? Tried to seduce someone? Snuck into some place to just steal something without really planning to get in a sword fight?
Does the body of the rules and what is written down pull us too much in a given direction?
Do player expectations and "party based play" force us into directions that limit our games?
What are the odds of an orc taking a bribe? What about a wood elf, a gnome, a troglodyte? Ever notice that's not in the rules? Oh sure you can hand wave it and base it on sensible decisions and likely outcomes...but uh...we don't do that for combat do we? Folks will tell you that's because combat is full of variables we are unfamiliar. Frankly folks, I've never bribed an orc or an elf but supposedly I'm qualified to make a judgement on how successful a bribery attempt is likely to be while I'm not competent enough to figure out how a combat would unfold (I have been in dozens of real fights and hundreds of fake fights however). Where is the separation really? Why can the basic setup of old-school play accept I can figure out if someone will take a given bribe without resorting to mechanics; sure I could use the reaction tables but that's more my learning how to adapt rules on hand than using the rules as written. No one complains If I simply say "oh 50 gp the guard takes it and looks the other way" no one will challenge that, I haven't done anything wrong but if I or any DM says "your henchman flops to the ground with his throat slit" without rolling any dice almost everyone will react poorly even if i know the 10th level thief was almost certainly going to waste the 1st level fighter with 5hp.
Can the halfling thief distract the dragon with a game of riddles while the rest of the party sneaks away?
Will the ogre settle for a few swigs from a jug as opposed to getting in a fight (would the players even bother)?
So what's the threshold for DM decision over dice for you?