Dorian's greatest contribution to bodybuilding was his understanding of training. He impacted the way we train today more than any other bodybuilder. Most people train each muscle group once/week nowadays, thanks to Dorian. Mentzer was preaching less volume and frequency in the 70's and 80's, but it wasn't until Dorian came along that everyone realized you can actually win a Mr. Olympia and be very dominating on such a routine.