Mine feel larger from doing pe for sometime. I think especially after doing weighted erect kegels. I think the reason is that it requires more hormonal support for the penis to remain erect. I also think that extensive edging helps, because that also probabably requires more hormone production. In some other book, I read someones suggestion that you alternate between periods ejaculation, and times without ejaculation. That way the testes have to produce more sperm, and than store more sperm. Interesting theory, but I don’t know if its true. I generally do through cycles where I feel like sexual activity, and times where I don’t so, maybe that has helped me.