To use back tension and back muscles properly, I think that the "let-off" of the bow has to be low to create that tension. Do you know the "let-off" you use on your target bow and what the ideal let-off is ? Thanks again for your great videos !
I really think this will vary from archer to archer, and even bow to bow too. On my PerformX3D I'm running 83% let off and I lock myself in at full draw with my back. This is a lot more let off percentage than I've ran in the past though. I was hovering around the 70-75% range for a long time with other bows but for some reason I hold better, indoors atleast, with this bow at 83%. Assuming correct draw length and loop length, the best way to check let off percentage is to hold on target at full draw without shooting and see what your float looks like as you pull slowly against the wall and increase tension. If you really steady up doing this then I'd look at possibly lowering your percentage of let off and raising holding weight. If you hold worse, then you could possibly raise the let off percentage and lower the holding weight to see if this holds better for you.
There's only a few Hoyt approved presses for the HyperEdge. The Last Chance Archery EZ Press is what I use and I ordered the Ultra Lock Adapters to go with it to be able to press the HE. Here's a link to my website for the press, and the ULA's are on it as well. www.rcrchery.com/last-chance-archery