The Linux development effort, Extreme Programming, and several other communities have bourne this out without neccessarily taking the same path of discovery. Peer review and letting a code snippet speak for its own quality are known to be good things. This gives us some additional insight into reasons why.
in reply to What you refuse to see, is your worst trap
I actually think that there are other reasons why regular peer review of code is good, too. Sometimes, no matter how much ego you get out of the way, starign at the same problem too long just keeps you from finding the source of it. You look somewhere that looks like the source of the problem, build a conception in your head, and can't look anywhere else to find the bug. This particular problem happens even when you didn't write the code. Sometimes a fresh set of eyes is just needed to break you out of a rut.
Christopher E. Stith