I remember specifically P4 was vastly overrated by Intel, where Athlon was actually generally faster at math, Intel used specially compiled code to show P4 was faster.
But there were several examples where Intel cheated, because Athlon was way better than P4.
I even went so far as to make my own test program, to see what the actual speeds were. I was an IT consultant, and was frustrated that customers were convinced Intel P4 was better than Athlon. And they also claimed Intel was more compatible, which was so annoying, since Athlon was actually more backwards compatible than P4.