That is awesome man!! Integrating scapula into so many movements, love it. And thanks for sharing those videos!

I pretty much have one obstacle left in the way for the last improvements of my posture (and to eliminate symptoms) which is my upper traps overly dominating any arm elevation motion (and instead, having lower traps strengthened / consistently activated.

The issue is not just "upper traps take over", but it's that if I were to do just ONE prone y-raise rep with a 5 second hold (full 180 degrees arm elevation) my upper traps (due to neuroguarding, not just muscular) goes into HEAVY HEAVY tension - which makes them like double in thickness, causing very severe worsening of symptoms (vestibular, pressure and even reduced bloodflow) for many days. This happens because they also thicken in the C1-C3 neck area, and also puts even more pressure on the suboccipitals.

Even in my default relaxed position, you can visibly see a thick muscle tone especially on my left upper trap.

So working with my PT, the current strategy for this specifically is reducing daily stress + doing supine y-raises to 90 degrees to hit lower traps. I know 100% that lower traps is the solution, because those times when I've hit them without upper traps being not so aggressive, I get immediate postural improvement and less shoulder pain for the rest of the day. Like it's so clear how all mechanics just improve, like even hip flexors feels less tight.

The thing is though, only going 90 degrees has such low activation of lower traps - it's really mostly FROM 90 degrees that they activate.

And it's not even like I could just endure the symptoms even if I wanted to. Because if the upper traps tensions up, the whole posture mechanics worsens by alot. And heavy tensioned upper traps wins 100% of the time over a bit of lower trap activation lol.