My roommate and I decided that we are going to try a double stimulation approach combined with the 5-3-1 method for increasing our main lifts. Our goals are pretty simple: get stronger and pack on some serious size. The only question that remains is with regards to volume. For the "main workouts" after the feeder circuit sessions, about how many total sets would you consider to be a reasonable amount? Or, maybe you think that keeping it under a certain amount of time (45 mins, for example) would be ideal? Also, should the volume vary depending on the muscle groups being targeted (for example, more pulling volume than pressing volume)? Lastly, we are both very busy college students... Does this approach only work if we can stick to the 4-on-1-off schedule religiously?