I have said this before - people should put their name in the actual block of code - I have code that I don't know who it was written by. However, some people who post their code may not care whether it is used or not - who's to say they wrote the code in the first place?
Some of the demo code that I saw being distributed by PC Format had the original credits removed - I'm not sure who by - One example was "Rob's" cubemapping demo - Originally, it had a disclaimer in it - now the disclaimer is gone, but I'm not sure if "Rob" removed it or someone else did.
I think it is best that people specify their disclaimers in the code.
Some of the demo code that I saw being distributed by PC Format had the original credits removed - I'm not sure who by - One example was "Rob's" cubemapping demo - Originally, it had a disclaimer in it - now the disclaimer is gone, but I'm not sure if "Rob" removed it or someone else did.
I think it is best that people specify their disclaimers in the code.