Hmmm... Actually that might be more complicated. First of all, not all situations are equal. Roberts has a situation bonus to Reason and a penalty to the other ones. So if you have one character with 2 in Charm, and the other guy has 1 in Reason, which one gets picked to do the talking? Second, there's no guarantee that the person who gets picked for the higher stat is going to pick the option that matches their high stat - they could pick something else.
Or one more layer of complexity, the party could be separated at the time. With the ability to split the group I think dialog needs to remain tied to the one doing the talking only.
Now what would be handy is the ability to select your other character without exiting conversation.
