Re: opening /tmp//foo doesn't work.

[Richard M. Stallman]

    So I would like to suggest that if opening /foo fails emacs will
    s|//|/|g and then try to open /tmp/foo, and if that fails will
    report that /foo and /tmp/foo do not exist.

It won't work, because `/tmp/' is deleted in the minibuffer
before Emacs ever tries to open a file.

That is a very important feature, and must be enabled by default.
However, it could make sense to turn off this feature when
insert-default-directory is nil.  Do people think that is a good idea?