I couldn't do it naturally in 6 months. On as, Ive nearly doubled my bench press max from 200 to over 400 in 8 weeks...I was much younger and may have blew my chest out on that cycle.. Lol. Also it depends on ur training level. Beginners usually add Strentfh quickly but others sometime get weaker
Imo, I don't think chin-ups would injure ur shoulder. If ur training for endurance, then form isn't that important, esp if ur explosive performing the excercise. If symmetry and working the entire muscle group for aesthetic purposes is ur goal or if the exercise has become too easy, then form is...
I have the same problem. Genectics, years of heavy chest routines and poor balance resulting in lack of symmetry. It's not gyno, which develops under the nipple. I think too much milk also contributes to fluid retention in the chest area.