It seems like the introvert/extrovert split, where few people are near the poles and there's a lot more going on in the middle.

E.g. I might check if someone has weekend plans before asking if I can stay with them. Or, I might ask outright, but specify it's not important, I just want to catch up, and the nearby hotel looks nice.

These seem like important differences even though they're both in the middle of ask and guess.