brianrex,
My difficulty has been the opposite of yours. Girth has come quite easily for me (thus far!). And I haven’t even really been trying for it. I’ve gone from 5" EG to 5.5" EG in the past few months. On the other hand, length is an absolute bugger for me.
I would contribute most (if not all) of this girth increase to clamping. I also jelq, but I don’t think this has contributed as much. However, my method of clamping is different than yours. First, I no longer use a cable clamp, which it seems from your pictures that you use. I now use a hose clamp. I think this is what it is called. You know, those metal clamps you find in the plumbing section that you have to screw down.
Second, and more importantly (I think), I don’t clamp behind the balls. I clamp in front of the balls, at the base of the shaft, as far down the shaft as I can place the clamp.
Specifically, I’ll achieve a full, or nearly full, erection first. Then I wrap 5 or 6 layers of ace bandage around the base of the shaft. I then place the hose clamp over the ace bandage and tighten. I use a "nut driver" rather than a screw driver to tighten/loosen the clamp with. (A nut driver is like a screw driver, except that it has an end for nuts, not screws; the clamp I use requires a 5/16 nut driver.) The screw driver slips easily and is therefore a bitch to use. As I’m tightening the clamp, I push and hold it as far down the base of the shaft as I can. This produces quite a stretch throughout the shaft; it also allows you to engorge more of the shaft. I tighten the clamp pretty far down. I’ll also tighten it more throughout the set. I limit my sets to 15 minutes, from when I have the clamp on.
I’ve tried clamping behind the balls. But in my experience, this is not nearly as effective as the above method. Also, at most I clamp one set a day average. Some days I’ll clamp two or even three sets. But I don’t clamp every day. So it probably works out to 1 set a day, 4 or 5 days a week average. As I said, girth hasn’t been my focus. I just like clamping.
Lastly, sometimes when I am clamping, I further squeeze the shaft of my penis with my hands and do some VERY GENTLE erect bends. My aim in squeezing the shaft is mainly to force more blood into the glans. But I’ll only do the additional squeezing and erect bends if my penis is not maximally erect. That is, I’ll only do them if there is a bit of flex in the penis. If the penis is very tense and tight, then at most I’ll gently massage the shaft with my hands while clamped.
I hope this helps. If not, you might want to consider the exchange I’ve offered on this thread: Anyone want to trade length for girth?