Too many variables; the program is not for everyone. However, the results if you actually do it AS WRITTEN have been phenomenal. If one saw the results we've had, both in terms of size and strength, most would say I was lying.
Of course, one has to commit to doing things correctly and believe in what they are doing. These two things, along with perception of limits/boundaries, play a bigger role than the program. Lots of people stick themselves in small cages, physically/emotionally, and can't figure out why they haven't grown.