Actually, thats not what I am saying, but I'll respond to each of your points:
Saeviomagy said:
So you'd be perfectly fine with someone who'd memorised all the monster books reciting out stats whenever his character met something?
Um, no. I'm talking about skills that are real life skills for either characters or players. For example, I am a neuroscientist, so recalling a pertinent detail about synaptic transmission and how it relates to thought generation would (in game terms) require a skill check. However, in real life, no one really knows the numerical mechanics (read- all the physics) behind this phenomenon. Likewise, PCs might have some lore or info about monsters, but wouldn't know numerical characteristics as such, since those numbers don't exist in the game world (DR, HD, or AC for example). Players memorizing stats from the game is clearly metagaming, and should not be permitted.
Saeviomagy said:
Or for that matter the guy in the group who does rock climbing being allowed to do some rock climbing in order for his character to succeed at climbing?
While I might give the guy a bonus for describing exactly what he is doing to climb a cliff, its simply ridiculous to make him climb a cliff to have his PC pass a skill check.
Saeviomagy said:
Or for one of the guys in the group to beat you up in order to win a combat?
Again, combat is a trained skill, which few modern people are familair with. Using an abstraction like D&D combat is fine here.
Saeviomagy said:
And furthermore, you'd consider anyone who didn't attempt these to be a 'powergamer' with no interest in roleplaying, regardless of whether he's any good or not.
'cause thats the equivalent of what you've just said.
I'd think the guy who wanted to climb the tree IRL to show me how his character did it was spastic and probably a little unhinged. Someone who memorized the stats of all monsters and spouted them off wouldn't be welcome at my table if he continued to do that after a warning. And RL violence isn't tolerated in my social situations, ever. These are things few people have much experience with IRL, so we have to rely on abstractions to decide how much a battle axe blow hurts, or exactly how difficult it is to scale a rocky outcropping in rain and a 20 mph wind.
These examples you give differ substantially from social situations in game though. First, barring the possibility the player is one of the unwashed, socially inept gamers, all people have some experience speaking with others and should be expected to at least ATTEMPT to role-play through what their character is saying to accomplish his goal. So I don't think it is at all unreasonable to ask a player to roleplay through the dialogue his character is using to influence others. It doesn't have to be a brilliant Shakespearean monologue, as long as some effort is made. A non-attempt (like I detailed earlier) would result in an automatic failure in my game, no matter what the roll was. Simply relying on the numbers strikes me as supremely lazy on the part of the player, and while it might be ok in a less roleplaying intensive game, it won't fly in my game. Each DM has to make that distinction for his game though. To me, it shows the player isn't even willing to expend the energy try to view or experience the world from his character's point of view, and its rather insulting to the DM since he spends a lot of time prepping for the game every session.