After reading the interesting debate regarding HD I was just wondering, before I switch to it: Did anyone find it successful and gained the gains Mentzer claims there should be?
I will tell you about my experience with using Heavy Duty is that I was more than pleased with the gains. I used it for a stint of nearly four months once, and again for about 2.5 months. I consistently gained strength while using HD. I also saw a noticeable increase in my vascularity which has stayed with me, whether or not I have had the chance to train. A few months after each training stint, I noticed an increase in bodyweight and muscle size. (I went from around 205 to 218 with that 6.5 months of combined training). That is >my< experience with HD. Limited, but it proved useful (and more productive than all of my other training in the past, which was much done much more consistently, but with slow and spurty gains, not optimal).