Hey All,
New to the forum, but I saw this thread and wanted to throw in my 2 cents.
I wanted to comment on the big troll with low Charisma not being able to use Intimidate effectively. I've always looked at it this way: If the Troll has a low Charisma, he might think he is saying "Listen you little puke, if you don't tell me what I want to hear, I'm going to rip off your head and give you an enima with it.", but what the intended target is hearing is "he he, can you tell me what I want to hear? No, oh that's too bad, I really wanted to hurt you, but since you don't know what I want to know, I guess that's ok."
You have to remember that Intimidating isn't just convincing the target to give up the information, but also a matter of tricking the target into admitting he knows the information that you want to know. Just watch any television show where the police are intimitading a perp. Sure they can't intimidate with physical, but they still have the weight of the law behind them, which is intimidating in and of itself. However, they still have to get the perp to own up to the fact that he knows anything at all. A low Charisma Troll would easily believe that the target doesn't actually know the information.
If anyone remembers the show Night Court, Bull Shanon was the perfect example of low Charisma but intimidating size. He could be intimidating to the average Joe (because of the size), but certainly not towards someone more charismatic. He would easily be fooled by his intimidatee.