I will add more here later…
Every paddler could make use of watching these videos. I found them during my curious research about paddle feather a few years ago.
Hand alignment and fixed control hand for feathered and control hand shift for unfeathered paddle
https://youtu.be/cOZnEPXt5ZE
How to set feather angle for neutral wrist alignment corresponding to your own individual paddle stroke geometry
https://youtu.be/1p7EW04RKAk
And my arty sketch for wrist alignment and distributed finger grip.