I don't know, it seems a bit vague to me... I was going to suggest the same thing with luck (like getting out of tricky situations, etc.), but then I thought about it and decided that in text-based RPGs like ours, skills like charisma, luck, attractiveness, and trading are simply not playable.
So, charisma would give a bonus to companions (when you're in a group) and affect the strength and duration of non-damaging spells (like blessings, prayers, and various summons), so charisma is needed!
Нет невежества - есть Знание