I had some extra time on my hands and went about testing performance differences with wow-64.exe using spoofed CPU ID's using Vmware and found some startling differences.
In laymans terms this is reporting an AMD CPU as an Intel Core I7 to wow-64.exe
Without further ado here are the WOW performance tests done on a Interlagos 8C/16C vs Core I7 3960X with spoofed CPU IDs.
No CPU ID change:
AMD --> 76min/102max
CPU ID spoofed:
AMD --> 127min/162max
Im not sure exactly how you guys optimize the compiler in terms of intel vs amd but the results are rather interesting.