Re: ! in Dired--what was the outcome?

[Richard Stallman]

    Actually, the problem concerned mainly `?'.  So if we decide to stick
    with this solution (assuming somebody would be willing to implement it
    and solve all other problems that need to be solved first to make it
    work), it would actually be `?' that should be bound as described
    above.  `*' could either be left alone or bound similarly with a
    display property of "<list of files>" or whatever.

Would you like to try implementing this?

    But then Juri pointed out that several other problems needed to be
    solved before this could be implemented.  I believe you then decided
    that these other problems should be solved.

Can you find what those other problems were?
Do they apply to the precise proposal which is to do this with ?,
rather than with *?