Re: pre-command-hook not run for DEL

[Richard Stallman]

    Yes.  And the only way to do it right is to completely re-implement it.
    E.g. redo it the way delete-selection-mode does.

I would not object to reimplementing it, but right now I'd rather fix
what can be fixed with small changes.

      Those people who want this kind of behavior
    will probably prefer delete-selection-mode anyway.

The purpose of mouse-region-delete-keys is to give beginners _by
default_ a behavior that they are accustomed to from other editors.