In my book, there's a deep, deep challenge in RPing as a medium, and this is kind of it.

"Charismatic" requires the one who is charismatic and the one who finds them charismatic. In order to prove your character is charismatic, another IC character has to find them charismatic: therefore, you have to invent a character to be a plot device or explain to another player that you're supposed to be charismatic. Neither is an ideal solution. It's a similar story with "smart", acknowledging that there are different kinds of smart; assuming it's book-smarts about a given universe's magic system, you the player need to know everything your character knows about the universe, and clarify that your character has an above-average access to that information.

For either of these traits to definitely manifest in an IC where characters actually interact, you either have to be in a really cooperative group, where people want to help you to tell your story (and where in return, you should do the same) - or it's Godmodding: "My character is officially charismatic and therefore your character should be persuaded" won't really work.

I'm reminded of a game on another forum. My character was basically a slacker and a coward, and had some information he wasn't letting on in order to avoid taking any responsibility for fixing a given situation. Another character, who had no possible way of knowing that he was concealing something, immediately rounded on mine when I mentioned OoC what he knew, and tenaciously pursued her baseless hunch based on the fact that she had the written the word 'perceptive'. The player clearly wanted to make good on her Character Sheet, which promised a [s]total Mary Sue[/s] character who was clever without realising that firmly sticking to her guns put her firmly in godmodding territory. Character sheets don't translate directly into the IC.

I'm also reminded of another game, before the guildfall, where two players kinda wanted to put their characters forward as the 'big guns' of the group. Mine was more of an aggressive, arrogant ace archetype; the other was more of a hard-working team player with a flair for battle. At first we kinda felt that they were mutually exclusive, but, when we talked about it, we found that we could both tell really interesting stories about powerful characters. To begin with, we agreed that my character would be more powerful (or at least, win encounters), giving the other character the chance to prove her hard-working team-oriented nature, and eventually surpass mine, at which point my guy could learn a very important lesson about the power of friendship.

I know people disagree about this, but I firmly believe that for certain games, everybody talking about their characters and kinda what story they want to tell through them is an effective (I won't say "best") way of preventing player-to-player conflict and helping people to work together to tell the stories that interest them. You can't use charisma on a character that is too suspicious. A smart-alec grade-schooler with a high iq probably won't outwit their headteacher if their headteacher is a functioning adult. Character sheets are good indicator of where you are and where you want to get to, but, in my book, you need to talk to each other in order to actually plan your route. Otherwise, cross one set of fingers, stick the other set up your ass, put on your astronaut helmet and run around your living room shouting the word [b]optimism[/b] because otherwise you're really just hoping for the best. I appreciate that some people like to play this way but ... ahem, I'm not convinced by the 'hope for the best' route.