FrozenNorth
Hero
And if you roll a 1 on your Climb check, that is what happens.I take it you haven't climbed a lot of rocks? Because unless you have information about a rockface there are plenty of times you don't know if it's solid granite or shale that will break off or an unpredictable aggregate. I don't see a reason it should be any different in a game. I'll let people know if they can't tell how easy the climb is and then it's up to them. No guts no glory.
But most cases, it seems to me that a character that is trained in Climbing has a pretty good idea of how difficult a climb is.