Can't someone dig into the MediaWiki code and have full dates display according to the preferences no matter what format they're in even without them being linked? That would solve the whole thing.
I think it would slow things down too much, as the code would have to read every page looking for dates, rather than just looking at links.
I did read something on this list a couple of weeks ago about a possible new way of marking dates... I can't remember the details.