It seems to be that it would relax some muscles within the penis and make for better stretching .
However, my routine still consists of basic stretching , A-stretches , and wet jelqs to finish things off. I do my jelqs wet, because I am more concerned with length than girth. However, I wonder if I would have trouble maintaining enough erection level to do my jelqs ? And would it be detrimental to whatever girth gains I might get? Right now, I'm not shooting for girth gains, but I would happily take them, as I eventually want about another 1.5".
I feel it makes the penis more pliable, it feels much stretchier for lack of a better word. It also is much more fatigued, PC muscle in particulat, which is why you feel the stretch more down there. Plus it helps keep unwanted erections at bay. As for more gains...probably??