It surprises me how stupid the AMD marketing team is. They used to have PR system for their products before and gave it up. Now they are repeating the mistake.
I am not a CPU architecture expert, but I know each CPU has quite a lot of frequency synthesizers inside. All of them use “master clock” signal to generate additional clock signals (with different frequencies/phases) for various CPU modules.
If Athlon does MORE per clock cycle than P4, then all AMD has to do is to recalculate the coefficients for the additional synthesizers. Or (in plane English) put an additional frequency divider for master clock. In this case AthlonXP 1533 (which is PR 1800+ according to new silly naming) would actually run at 1800 MHz (or even 2 GHz) showing the same performance. And it will be competitive with Intel in both efficiency and “marketability”.
You think such trick is unfair? Well, who can prove me Intel is not doing that? P4 does LESS per clock cycle than P3