There are tons of people out there witty with text and digital chatting who aren't as verbally spry irl. There's a world of difference between typing something in the comfort of our homes, with the time and opportunity to ponder and edit, and being in front of people who we're trying to communicate a whole myriad of things to--not just verbally, but non-verbally, as well (body language, tone, etc). Likewise, I know people who are very witty and charismatic in verbal conversations, but come across like a brick in digital text. The two are in no way interchangeable and a deftness in one doesn't signify a deftness in another. Edit: We must also consider that stutterers are probably better in non-verbal modes of expression because we're people who are dealing with an inability to express ourselves verbally. Were we fluent, who's to say we'd be as good in text? And that doesn't necessarily mean we'd be just as good verbally. Instead, it'd probably be spread more evenly. (Of course, this is pure speculation).