You can see me shoot forward at the bottom of the second rep -- I felt a painful pop in my lumbar region just before then.
I have spent a decent amount of time attempting to improve my form with healthy doses of Tate, Cressey, Robertson, and Stuart McGill, but clearly I am not there yet.
I'd say my biggest uncertainty involves core tightness and trying to incorporate all of the concepts I have come across. In particular, I am a little confused with how to tighten my abdominals while at the same time keeping my lower back arch tight. These seems like competing moves, sort of like flexing triceps and biceps at the same time.
Any glaring form weaknesses/advice?