FYI -- i combine 5/3/1 and gvt.
i do 5 3 1, then my back off work is half of gvt, but i use about 70% or so and do 5 sets of 6 (i've seen 60% for 10 of 10, and 70-73% for 10 sets of 6 for GVT), so i'm doing 5 sets of 6 alternated with an opposite movement (so rows vs bench, pull ups vs chins...