In my 10+ years now as a Physical Therapist and being an archer since I was 5 years old I have tried to mend the two and see what I can come up with to help other archers. I have treated many shoulder problems and see common complaints from archers about shoulder pain developing as a result of shooting a lot.
Recently, I have developed shoulder pain while shooting anything over 30 arrows and, at one time, anything over 5 or 6 arrows would greatly inflame my shoulder to a point where I needed to rest it about 3 or 4 days before trying to shoot again. I have read everything here in regards to drawing a bow with back tension and I like the technique, but it has never helped my shoulder in regards to shoulder pain (trust me in saying I was doing the technique correctly). I have a theory as to why it did not help me and I will explain this later.
I have developed a technique that has really helped me and its based off multiple things 1) Believe it or not, pistol shooting 2) my education in biomechanics, orthopedics and experience in physical therapy for 10+ years now 3) my own shoulder pain and experimentation with what has worked for me. So I am going to explain this technique and would want to see if it helps those that have shoulder pain, either significantly decrease it or eliminate it totally, if it is solely caused by drawing and holding the bow.
To understand this technique to you have to understand the shoulder girdle and ways to stabilize the shoulder joint. The best way to stabilize the shoulder joint is to squeeze your shoulder blades down and backward. In doing this, you tie in your shoulder blade to your thoracic (torso) cage, making it part of your core musculature and it is very stable here. Most people that have shoulder pain have anterior shoulder pain from lack of lower trap, latissimus and middle trap contraction helping to stabilize the joint. This makes the bicep try to work as an anterior stabilizer of the shoulder, when it shouldn't work in that fashion. The biceps tendon gets very inflamed from impingement because the joint is allowed to elevate too far and pinch on the tendon.
One way I demonstrate this is to have someone lie on the ground face up and raise their arm up to the ceiling. Now, have another person try and pick that person up off the ground from their arm. You can see that their arm is very loose and their body slightly rotates when you pick them up off the ground, very unstable position. This is how most peoples shoulders are when trying to draw the bow. Now, lower them, have them raise the arm again, but this time squeeze the shoulder blades together (down and backward) and keep them like that. Now try and pick that person up and see what results you get. You will see that the person comes up as one now, no rotation, to protraction in the shoulder and the shoulder is very stable with the contraction of the lats, middle and lower traps.
Based off this concept this is how I draw my bow now and it has eliminated my shoulder pain completely. Its based off a push/pull technique developed in pistol shooting off the Weaver stance and the concept of stabilizing the shoulder BEFORE you draw. In pistol shooting, one technique used while shooting is pushing with one hand and pulling with the other creating dynamic tension which stabilizes the gun very well during recoil. So the draw technique I came up with is basically pushing with one arm and pulling with the other but stabilizing (retracting the shoulder blades down and backward FIRST), which differs from the back tension release (BTR). BTR wants you to use your middle trap to draw the bow, but it doesn't stabilize your shoulder from a biomechanical standpoint. The middle trap/rhomboid is a stabilizer, not a prime mover of your shoulder, thus it should not be used as a prime mover in drawing your bow, IMO.
So here is the technique, basically your stance is the same, you bring your bow up to shooting level with bow arm bent, squeeze your shoulder blades together FIRST to stabilize, then push with the bow arm extending the arm and pushing away from you with your chest and simultaneously pull your drawing arm backward to full draw, keeping your shoulder blades retracted the entire time until releasing the arrow. This way you stabilize your shoulder BEFORE even drawing the bow and using push and pull technique with opposing forces your essentially draw the bow using both sides of your body. Bow arm will use the pectoral muscle or chest and tricep, and drawing arm will use the latissimus, middle trap and bicep. Both shoulders are really stable and not allowed to go into areas they shouldn't causing impingement issues.
Try it and see if it works for you.