Well, the author of Test::More seems to differ on that: <http://rt.cpan.org/Public/Bug/Display.html?id=8391>
Although personally I'd think I'd read into that, that forking shouldn't cause problems, with "and you should be able to emit test output on both sides" as a bonus extended DWIM feature :)
But then most of my nervousness is a defensive reaction, the mere WORDS "fork" and "IPC" send my mind into platform edge cases hell.
Adam K