I’ve been reading through your log and seems like you are thinking about testing similar girth protocol that I’ve had in my mind for quite some time.
Applying same principles which are discussed when it comes to length-oriented gains but with pump usage and targeting girth.
Water pumping seems to be the best idea. Its non compressible and has high heat capacity.
I can see, that reaching proper temperatures is problematic with erected penis, and for sure especially with bigger girths, but proper pre-heating (with US for example) and then going straight into pump with water warmed up to therapeutic temperatures could be quite effective.
Also with slowly increased pressure it should be possible to avoid any significant edema during pumping. The best option would be some kind of electric vacuum pump that could increase the pressure in a controlled manner to maximize expansion and limit edema. That would also follow the rule of slow-strain that Tutt was writing about in a different topic. Guess it is still possible with hand pump device, but not in such a smooth and controlled manner.
What is your view on this topic? Are you planning to add chemically induced priapism in order to keep max erection during water pumping?
Also, I just guessed that you are going for smth like this, so excuse me if I went too far with my assumptions