I got the serious growth program back in the day as well. It looked good on paper but had a few flaws:
Training ever set to failure and training each muscle group 3-6 times a week. I think that you can work up to trianing an exercise 6 times a week, but you have to avoid failure and regulate volume.
Too many workouts throughout the week in which you did 12-15 reps. Great way to burnout.
They came out with an updated version around 1994 which had a program in which you hit each muscle group 2 times a week and workout 4 times a week. You would gradually go through phases in which you hit the same muscle group more frequently and then cycle back to 2 times a week again. I made some modifications with this workout regimen that worked well for me. Instead of doing 12-15 reps on a few day, I never did more than 8.
One one day I would do sets of 8, and use the same weight on all three sets. On the last set, I would shoot for 10. If I got 10, I increased the weight at the next workout. Another day, I would do sets of 5 and then another day do sets of 1-3. I cut out isolation exercises as well such as tricep and bicep work.
My bench and deadlift went up fast and I went through phases in which I got much stronger at each workout for lenghty periods of time.
Like any training regimen, you have to personalize it to your goals and your recovery abilities. I like the micro-cycle concept in Serious Growth and there were a few other good ideas as well. Steroid like growth? I don’t think so. However, it did work well for me, when I changed a few things around.