For the timing of the shift, does it come at the apex of the reachback? Essentially, should weight be shifted totally to the lead leg, with rear leg deweighted, before the upper body begins pulling the arm through? This is how I've been thinking about shifting from behind, because at apex of reachback the back is fully to the target.
In reality it probably happens more simultaneously, just trying to figure out what my mental picture should be.
Also, I had some throws in my most recent practice session where it felt like I was shifting my weight at a 45 degree angle to the left of the target line, and it felt like it was counterbalancing my arm on the right side of my body (LHBH remember). I'm not sure this is right though, but it got me thinking about weight shift direction. Should the shift feel like it's headed in the direction of the target or is it angled to the target to counterbalance arm weight swinging through? It seems like crushing the can/heel planting is already a directional shift because it happens sorta perpendicular to the target anyway and you have to move toe to heel, but I could be understanding it wrong.