This is an interesting debate/comparison that I am still not convinced about which method of loading is more effective. I guess in a way it boils down to your classic argument of a high intensity set (as a % of 1-RM) as your top set versus multiple sets with a moderately heavy load.
On the one hand, when you pyramid up in weight over several sets, you are able to challenge your muscles with a max effort type of load for the final set. By using straights sets, however, you provide a greater working volume but do not lift that ultra heavy load to finish.
I have noticed that most pro bodybuilders utilize the pyramiding style but many coaches seem to favor multiple sets. I am just sort of curious as to what most of you have had the best results with in regard to strength and size?