I have never seen any substantial growth from high reps, I can see a get increase in endurance but to add size, I do not think that would be recommended. It all comes down to your goals. Huge mass or a toned body. High reps to me are more towards toning ones body. My 2 cents! Progressive resistance will not allow ones body to become accustommed to it, it is constantly changing through the weight increase, forcing the body to grow and get stronger. I always stick to heavy weights lower reps now, in the past when i trained in the 8 - 10 rep range my gains slowed dramatically. I am trying out the Max OT workout right now with great success, nice heavy weights, high intensity and you aim for a rep range of 4-6 reps, to positive failure! In the last week alone I have put on over 5 pounds, still maintaining my definition.