[HappyCatMachine]

From a cognitive viewpoint I'd hate to have to deal with that. Every time I felt inclined to hit return I'd have to interrupt my thinking process and down arrow instead, or tap the screen. When I'm writing I don't want to have to interrupt it to deal with that kind of thing.

I think composing in the notes field would work better but to each his or her own, of course. It's a reasonably good idea as long as you don't mind having to correct yourself before hitting return :)