I’m not sure what the going wisdom is on heating while clamped, but I personally think that’s something that could help mitigate the potentially disastrous injuries that I believe clamping is easily capable of causing.
I hope you can forgive me for beating a dead horse here, but I have to say this directly to you unhung1. I know you’re really focused and dedicated to making this work, which is great and I’m sure you can be successful. I’m just really nervous from the tone of some of your posts that you’re dancing with a serious and potentially devastating injury. Please remind yourself consistently not to approach it with the idea of being as erect as humanly possible and clamping down as tightly as possible and forcing expansion as aggressively as possible. I understand that impulse, but when I was exercising from that mindset I completely lost erectile function in my spongiosum for almost a decade. It’s only now starting to recover. There are real horror stories on this site and they can very easily happen to any of us. It’s not something to view as somebody else’s misfortune.
Just try to keep your exercises a few steps below maximum intensity and you will see much better results than you will if you try to force results through overzealous punishing exercises that will almost undoubtedly harm you. We are coaxing growth responses, and it’s much more like luring a turtle out of its shell more than it is like yanking the turtle’s head off.
Anyway, I know this is repetitious and more than a little pedagogic, but I’m warning people from a place a very negative and very real personal experience. Good luck.