This reminds me of a long battle I had with The Damian, where he finally acknowledged he made a boo boo in Perl Best Practices, due to his lack of knowledge of differences in behaviour of Perl's unlink function between Unix and Windows:

• Perl Best Practices book: is this one a best practice or a dodgy practice?
• Re-runnably editing a file in place (see also this related atomic rename node)

I'm pretty sure that's the only argument I ever won against him. :)