He's a idiot, go to any bench comp or powerlifting meet. Your back should have a arch so that your traps and shoulders are making contact with the bench. If your goal is to move maxium poundage then all that matters is safely moving the weight from point a to point b. Proper form is whatever position safely makes you the strongest for that particular lift. Ignore ignorant comments.Day 41: Woke up at 204lbs this morning and trained chest; didn’t have time to get in my full workout. Pretty much only did flat bench, but surprisingly I banged out a 365lb bench today raw. Received a few compliments today on my back width and even had a random guy telling me that I’m probably the strongest person he’s seen in my gym lb for lb. Also had a gym acquaintance of mine who is a cop tell me that my 365 bench didn’t count because I was arching my back and because I take steroids lmao. I just sarcastically replied “I’m all natural, you jealous bro?” Lmfao.