For pull ups/chins, I am aware that the arms should be fully extended at the bottom of the movement, but does this mean fully relaxed and as far down as you can go? Would it be better for the shoulders to have some tension and not let them shrug all the way up to/past your ears at the bottom?
For the bench press, is it possible for a flexible person to put too much back arch into the lift even if their butt is firmly planted on the bench and their feet are flat on the floor? By doing this an easier leverage is achieved but I am not sure if this defeats the whole point of a flat bench press. The angle isn't so severe that it becomes a decline press, though. I just find that it helps me get more under the bar if you know what I mean. I am pretty lanky and don't really enjoy benching all that much...
If you relax your arms at the bottom and let your shoulders slide down, the muscles that have to pull you back up from that position are the lats and upper back muscles. Since we want to work them, use the full ROM in the exercise.
And the better "legal" bench position you can squeeze into, the more you can bench. This is a good thing.
One thing I've been wondering is why on the bench press do you advocate a retraction of the scapulas to reduce range of motion, whereas in pretty much all the other primary lifts you advocate maximal range of motion? Why the exception for the BP?
But I'm thinking of your reasoning for not teaching the Sumo-style squat: our objective is to get strong (including the quads), not lift the greatest amount of weight. And also how you allow some hip extension and shoulder flexion in curls, making it a more compound movement.
Thus, I wonder why we don't make the BP a more compound movement that trains an expanded group of muscles?
Mark, I'm surprised by your answer on the pullups ROM. Unless I'm reading it wrong, he's basically asking if he should abandon an active shoulder at the bottom position. My understanding is that this is about the best way to cause shoulder impingement. Am I missing something?