Re: Shift-movement selection

[Richard Stallman]

    so cursor motion commands such as C-f would still not normally
    deactivate the mark, except when the mark was activated by
    a shifted key.  This is the desired behavior.

I doubt that such a broad change is good.

Also, it is rather painful to implement, since there are dozens of
cursor motion commands, if not hundreds.  Lots of modes have their
own motion commands.

I think the only reliable way to implement that feature--if we want
it--is to do it in the main loop, after the command returns, if it has
moved point.  But that hard-wires the meaning of non-shift, which is
very non-Emacs-y.