I started hanging a month ago, but I also do six sets of 30 sec stretches (straight out) in each morning in the shower. I do this as intense as possible, but I am wondering is they really help.
Many guys combine stretching and hanging. You just have to experiment to figure out what works for you.
Some PEers assume that hanging is the hardcore lenth exercise, and that if one fails to gain via hanging, he will not gain through any method, but this is not universally true. Modestoman, for example, did some pretty extreme hanging but never gained a millimeter from it; switching to a simple manual routine kickstarted his gains.
My guess is that the shower stretches you’re doing are unlikely to hurt your PE progress in any way, so as long as you don’t find them a nuisance, they may be a helpful supplement to your hanging routine (or maybe vice versa!).