Time to do some more reading here on Thunders.
RE: HGH, IGF, AAS, Slin… HGH is pretty much useless unless it’s used with T3 and Slin. Been there, done that. It doesn’t make the penis grow, neither does IGF-1. The receptors simply aren’t there past puberty. The only AAS that has been shown to cause penis enlargement is winny, and that’s only when used in pre-pubescent boys. The risks and sides of it far outweigh any benefit for PE.
I believe only benefit to these things for PE would be better erections for clamping and improved healing. I’ve not done a cycle since starting PE, but I do believe that considering that while on we become basically just walking, erect penises it would lead to better gains from clamping. Since we don’t want to be erect while hanging, it may be harmful there.
Chemical PE is a possiblity through the same mechanisms where we have better erections from it. Priapism will cause PE, but can lead to loss of your penis too so one would have to be damn careful if considering such a thing.
My time using the substances you mention DID NOT lead to any penis enlargement whatsoever prior to beginning PE. I’ve even asked on this forum if GH injected directly into the penis would lead to gains. Trust me, if it would work, someone here would know it because there is nothing that hasn’t been tried before.
Each of the topics you’ve mentioned have been addressed before. Do some reading and then ask your questions…you’ll get some help from the vets here. They’ve helped me a great deal.