4 sets of 20 with 315
thats quite intense...
intensity has nothing to do with reps and weight...
its to do with how hard you are pushing...if someone can do 8 sets of 20x315 in the same time that this guy does 4 sets then the 4 sets is 50% intensity...
if your max heart rate is being hit or exceeded thats a better measure. if you spew, opr are about to spew, or take a long time to get heart rate back to 120 or so then you are working pretty hard..
going to failure and having minimal rest and keeping reps reasonably low is intense..regardless of the weight used.