i don't see what catchweights have to do with being P4P.. pound for pound means best regardless of weight.. doesn't necessarily meant weight CLASS..

on top of that, with catch weights it should be even EASIER to help determine who is P4P best considering you're not ONLY limited to your weight class and you would not have to hypothetically say, i wonder who is better between this welterweight and junior welterweight.. well they can meet in the middle and fight at a catchweight.

P4P becomes more difficult to figure out when you have guys who could never fight each other, and who dont have common opponents..