Unit Testing
I'm a victim of something. Probably television advertising during my more impressionable years. I prefer UPS to FedEx; Pepsi to Coke; McDonald's to Burger King. But I don't regularly ship things; I don't drink soda; and I don't eat fast food. So they're almost meaningless convictions, but they're still there.
Somewhat related, I hate Unit Testing. It's not flawed in theory; it's flawed in practice. Like C++. In my several corporate experiences with unit testing, it was evident that it was used as a substitute for basic software engineering competence.
So there's this entertainingly blunt blog post on the topic of unit testing stupidity here. I can't believe I'm linking to MSDN.