When I was assisting back in the 80's, nobody used ball heads with 4x5's and 8x10s. Well, it was 99.9% studio work anyway.
Now that I'm using these formats for my personal stuff, I noticed people with 4x5's really want to use ball heads. Is it just sexy to use? I try it on my Cambo 4x5 (its pretty light), but I really don't see much of an advantage.

BTW, I'm home from oral surgery and taking vicodin. Maybe I'm just being a little silly today.