Divide and conquer
It seems a lot of guys are confused about hanging directions and how to hang efficiently.
Once again, there is no true single best way to hang. It is completely individual. You must learn to feel what is needed, and the feel the best way to go about it. But here are some general guidelines.
First, you must stretch some skin. Skin is the first limiting factor because of the slide-ability of the skin. The bibhangers have the capacity to grasp internal structures to prevent or reduce the amount of hanger slide, but in general, there will still be some. This means the skin will usually take the brunt of the stress in the beginning. This is ok, because you must stretch some skin in order to accomodate the future internal shaft gains.
Further, it is much easier to only stretch one at a time. First the skin, then the internal shaft. I used to do this on a continual basis by varying the hanger attachment point. More toward the head would stress the internal shaft, more toward the body would increase skin stress. Divide and conquer.
This same principle applies also to the ligs and tunica. There are two different bundles of ligs, the suspensory and the fundiform. The suspensory are what everyone talks about generally. They are below the surface of the skin, running from the pubic bone to attach on the tunica. I think of them like the support cables running from the body of a crane to the boom of the crane.
Anyway, varying angles between straight out, and BTC will stress different connective tissue bundles and even different individual fibers. Even a change of a couple of degrees of the hanging angle will give a different stretch. This is what I mean by divide and conquer. If you try to stretch everything at the same time, using the same angle all the time, the tissues fall into equilibrium. All roughly taking about the same amount of stress. Much better is to make one area take the stress during a set or session, then make another area take the stress in another set or session.
I have always said BTC is the most efficient angle for making gains. It will put the most stress on the susp ligs, which should generally allow for the most gains. However, you cannot target this area alone.
I estimate that I hung between straight out and BTC maybe 80% of my hanging time. Depending on how far down in my chair I scooted, I had maybe five or six different, seperate angles of hang that worked different areas. Divide and conquer. The other 20% was OTS and OTL. This was when I was fatigued hanging at the other angles.
Anyway, if you are doing the same thing, at the same angle, every day, change it up. When you no longer feel the work at a certain angle, you are wasting hanging time. Rather than first going up in weight, first try a different angle. I estimate that for most guys, there are 270 vertical degrees of possible hang. Then there are at least 180 degrees of horizontal hang, giving an almost infinite number of two dimentional angles of hang.