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They weren't necessarily short - I don't remember the exact specifics of all of it, but some of them were missing a little left or right or both. Day 1 they were landing on the edge and kicking on, where day 2 they were just missing and kicking down into the bunkers and did it a lot. I think all told I actually went into bunkers on 8 holes. Some of them were not good shots. Like a few examples, on 8, the pin was in the back. I hit it solidly, but pulled it and it went long, over the bunker into long grass. I had the ball in sandy earth with long grass around it and about a foot below my feet. That next shot I tried to do what I could but it went into the bunker in front of me. Into a footprint. That one I dug out of the footprint, but still in the bunker. Got that one out of the bunker, but into the fringe grass in front of me. Chipped that one on a bit hard and two putts later made a 7. Another was on 14. The flag was on the little finger of green front left. I tried to play a little past it and a little right. Shoved it maybe 10 yards right of where I wanted to and the carry over the bunker gets longer the further right you go and that one hit the grass between the green and the bunker and came back down into the sand, left it in there and didn't get up and down on the next one. I think carrywise it carried about as far as I was planning on it doing so. Another was on 6, leaked my drive a little right into the fairway bunker. Hit a nearly good shot from there that went a little left and a little short and kicked into the bunker front left. That was a strike thing and just a hard shot. Did similar on 18. Drive in the right bunker, slightly heavy second that hit the bank between green and bunker again and kicked back into the sand. I think the tiredness manifested more as not squaring the face up so well and less as slowing down.

Depends on how short you were coming up on these shots. A bit more wind? Also, maybe you were swinging at 2-3 mph slower the next day.  I think the biggest thing is not adjusting. Like making assuming your stock shot is not enough and taking 1 club up. Not sure what type of adjustments you were making in your decision making. 

No one should measure a joint mobility away from that joint. If you go to physical therapy, they are not measuring your knee mobility based on your midline. It is based at the joint. Shoulder mobility should be measured in reference to the shoulder joint. 

He's using a driver swing, while I used the iron swing. Bryson goes from about 65° B to 15° B, hence the 50°. If you bend your right elbow, you're going to pull your hands across your chest some. Conversely, if you abduct your right arm and hold onto a grip with your left arm, you can see how extending the right elbow as we do in the golf swing during the downswing will "pull" the right shoulder/humerus forward (adducting it, as going from 65° to 15° of abduction is). Even people who pull their right shoulder WAY too far around them eventually get it "back in front" when their right arm/elbow extends. So, such a motion shows up as shoulder adduction even though the movement that causes it is just widening the trail elbow. The left hand on the grip almost "pulls" the hands forward as the left arm can't stretch much (there's some shoulder protraction, but that's almost maxed out at P4). Oh, I downloaded it and watched it (and commented there) before he blocked me. It's what led to him posting the comment in the "update" above. 😄  Single shoulder range of 75°, and that's going out well into the follow-through. 50° Max range up to impact. Manavian's video is bad. He keeps saying "midline" which is just a horrible way to look at it. He also kept saying that the club was moving that amount — also wrong. Adding left and right together is really freaking dumb. Another golf instructor said "That's like saying the player has 100 degrees of knee bend (adding left knee bend to right knee bend) 🤦‍♂️" (similar to what the biomechanist said about squatting). Also, see my post above about elbow bend. That's why Plummer’s alignment stick demo is so intellectually dishonest. A golfer can't get anywhere near that position on the left with his left hand on the alignment stick (quoted below).  

That makes no sense at all.  so, I watched that Instagram. Here is a summary...  Bryson.... Address: Trail Shoulder 0 degrees adduction. P4: Trail Shoulder 65-deg abduction. Impact: Right shoulder 15-deg abduction. P9: 10 degrees adduction. Rory... Address: Trail Shoulder 16 degrees adduction. P4: Trail Shoulder 26 degrees abduction. Impact: Right shoulder 0 degrees abduction.  P9: 18 degrees of adduction.  DJ... Address: Trail Shoulder 4 degrees adduction. P4: Trail Shoulder 42 degrees abduction. Impact: Right shoulder 2 degrees abduction.  P9: 15 degrees of adduction.  Their point is that arm doesn't stay on the trail side. That the arms have to get across the chest from P4 to P9. I mean they do. What matters is the rate of which it happens relative to the position of the swing. The trail shoulder at P9 is not abducted a lot. The range of that total abduction movement is like 40 to 70 degrees. Bryson might be an outlier. Rory might be an outlier as well.  A couple of points.  1. None of them had any adduction at impact. So, this tells me the trail arms stays on the trail side of the body at impact. Is it moving towards lead shoulder, yes. It doesn't happen till post impact. The right side of the body is moving towards the target, so the arms don't have to as much as people think.  2. Trail shoulder adduction from Impact to P9 is 18 to 25 degrees.  3. P9 adduction of the trail shoulder is only about 2 to 12 degrees more adducted than at address. The arms/hands stay in front of the chest a long-time post impact. If Rory, from his address position just rotated his body towards the target and raised up his arms so he is at P9. He basically didn't have to move his trail arm further across his chest than where he started at address. Visualize that for a bit. I bet for people who tend to stall and drag their arms across their body to hit the ball, that would emphasize how much the arms stay in front of the body and how much you have to turn.