> Just FWIW, there is an existing package which effectively uses the
> prefix "mc" - just following it with "/", it's called multiple-cursors,
> and it's been pretty popular a number of years ago.

Thanks, I hadn't seen that on MELPA, only its mc-* derivatives.

`moc' was the fallback plan.  It does not trivially complete together with
any `mc' symbols.  Anyone object to that?