Rmail conversion misfeature

[Richard M Stallman <rms@gnu.org>]

Querying before converting a Babyl file is misguided feature.
There is no way to proceed except to convert it.

I think the motive for this was to help people avoid
unwittingly rewriting Babyl files in mbox format.
I see the desirability of that goal, but this cure is
worse than the disease.  I plan to delete it.

I can envision a better way to achieve that goal: (1) mark the buffer
unmodified after conversion, and (2) change the operations that would
modify the buffer first warn you and query.  That feature won't cause
any hassles just to look at the file, but when you try to alter it,
you will be notified that this would result in changing its format
when you save the changes.