A similar optimisation was with tmux to bind the prefix to C-z. It's in a handy location next to ctrl and I very rarely use suspend anyway (which is still available as easily as C-z z). Stretching your fingers between ctrl and b (the default prefix key) merely made me wonder who the heck thought of something like this?
As for vi, I made a point of learning to use it enough to do useful work editing config files and small texts. Every once in a while another application brought up 'vi' for some reason (maybe I lost VISUAL or EDITOR while sudoing or the app was looking for another variable) and I could never exit the damn thing.
So instead of just learning :q and figuring out how to make the particular program or script relaunch another editor I thought it's the path of least resistance to just edit with vi directly. It has been an incredibly handy skill: I never use vi for anything larger but these days I actually do 'vi /etc/fstab' myself instead of calling for emacsclient.
However, I've been toying around with the idea of eventually writing a minimal 'vi' clone that you cannot exit. I'm sure there's pent-up demand just waiting for one!