I have the unenviable task at my company of improving one of the development team's set of coding standards. They're well known for being rather slimline and, in some cases, impossible to work out what they mean. But here's my favourite...
Section 4.1.6 states "redundant code should be deleted, not commented out."
Section 4.1.7 states "comment out redundant code; do not remove it!"
David.