I used to like Rich Piana a lot. I still in most ways. But so many of these guys known for no bullshit are actually the worst bullshitters. Some massive volume days using sparingly will be good for weak body parts but this is just plain silly. Rich was a great bodybuilder but his arms were his weakest body part in his prime (legs being the strongest). The reason he looks the way he does now is the massive amounts of PMMA injected all over (mainly in his upper body though). I have seen Rich in person and he looks incredible but take most of his videos with a pinch of salt. If arms are a weak body part then you have to play around with exercises and angles, volume and rep ranges. Another thing I highly recommend is injecting most of the things you use in your arms... that may be aas, lr3, des, mgf etc.