Progressive overload is ultimately needed for lean mass gains. However, anecdotally, and now with some scientific support, it seems like very frequent training variation may help speed up lean mass accrual (assuming strength increases is correlating with muscle growth).
I don't agree with Dr. Stoppani's recommendation to use massive rep range variation with exercise variation. Layne Norton and others have made good arguments for using 5-7 reps to concentric failure as a primary hypertrophy base (for tension stimulus) with higher rep training (10-12) as a secondary rep range for (fatigue stimulus) to increase TUT while still utilizing a good percentage of muscle fibers. There is hardly ever a reason to use 20-30 reps is a hypertrophy program. It is not a good hypertrophy range for numerous, very well studied and elucidated reasons that have been discussed ad nauseum.
What would be better than Dr. Stoppani's recommendation here, would be to use 3 or 4 primary exercises for each body part and cycle them WHILE USING PROGRESSIVE OVERLOAD. Thta is the key. Add weight to the bar with each cycle and you have the benefits of exercise variation/novel stimulation with progressive overload.