Being a player of the piano (as well as the alphanumeric-keyboard) this "digit" inversion does happen on occasion, but most often as the "notes" pass from one hand to the next, and usually when I am arrogant enough to think I have begun to memorize the computer keybord feel and type fast without looking.

I'm sure this has come up before (here on AWAD) but I can't find it... why is the computer keyboard (typewriter keyboard) laid out in the manner it is.. and has anyone ever suggested an improvement to this century+ old technology?