Here's my experience for what it's worth. The jelqing and stretching for the first five or six months seemed to benefit length and girth equally. Since then, I have concentrated on stretching and my girth has continued to grow, especially flaccid-wise. Length-wise, I have made little progress to speak of. I have always felt that the penis, like one of those long balloons, which grows in girth as you squeeze the air out of part of it. If there is a limited amount of blood supply, wouldn't the penis work the same way?
Here's why I believe this based on my experience. When I awake with a maximum woody, somewhere in the not quite 9" by 7" category, and its slowly subsiding, lying supine, I can edge it to 10" to 12" in length, but certainly not the 7" in girth--probably less than 6".
Is this not like one of those long balloons, that when you squeeze it at one end, you can increase its girth and visa versa?