=head1  Latent Problems

It appears that a the reason (contributing at least) that diags dont
match to croaks is because the printf substitutions that are there.

The =items are loaded into (my) %diagnostics::transfmt, and values are
initialized to a corresponding regex.  %transfmt is used in
diagnostics::transmo() by splainthis() to match against the actual
error and produce the message.

By using diagnostics, I think I can splainthis() on the croaks, thus
eliminating the ones that are matched by a diagnostics entry.