Norfleet said:The problem is, people expect diplomacy, even high levels of diplomacy, to operate like magic: That's not how diplomacy works. You don't simply wave your hand and tell them that these aren't the droids they're looking for.
That's the impression I get. Even if it's supported by the scanty rules given, I don't think it's what the designers intended - that a good Diplomacy roll acts as Charm Monster with no saving throw.
I do agree that in most cases Diplomacy should be usable and have significant in-game effects - at least comparable to a successful attack roll. CE Bandits changed from Hostile to Friendly would offer to let the PCs past with only a 'nominal toll'. To Helpful, they'd let the PCs past without charge and maybe offer useful advice on other dangers ahead. I can't see a DC40 Diplomacy roll persuading a Lich to hand over his phylactery to his arch-enemies, although he might be persuaded to reveal its location. I can't see even a DC100 Diplomacy roll persuading a Solar to switch sides and join the armies of Graz'zt - unless the Graz'zite Diplomatist had something good to work with:
"Oh, so Pelor turned you down for that raise again, eh? That's too bad..."