I am a hardgainer when it comes to pumping. Any size gains that I have experienced took years to achieve and my future gains are coming very s-l-o-w-l-y. I also have an anatomy problem with my penis that prevents me from pumping up to my full potential. I have a very high scrotal insertion which gives the underside of my cock a pelican or turkey neck appearance. This means that the base of my tubes always have some sac in it. That prevents me from getting good pulls length and girthwise to achieve mind blowing gains. I have achieved quite a lot of growth despite this pumping "handicap". Because of my high scrotal insertion, I only achieve about an inch of length gain when I pump and it will go away if I stop.
The only thing that is permanent about my pumping is that my skin's surface area is increased and can get bigger erections than I got before I started because I have a bit more skin to work with (I was circumcised VERY tight). Other than that, I haven't experienced much permanent gains from pumping.
I just know this because last year I had a thrombosed hemmroid that was sooooo painful that I couldn't sit down for almost 6 weeks. I couldn't pump at all because pumping requires copious amounts of sitting. I lost almost all of my pumping size gains after the third week.
If I was to stop lifting weights, I would probably shrink down to next to nothing in about two months.
Although, there is one kind of permanent gain from pumping that I have achieved over the years. I could only pack the 2 inch tube the first year that I pumped. I got a 2.25 inch tube and was only packing it about 85% at my absolute best pumps, but achieving only 75% packs most of the time. I wasn't able to achieve full 2.25 packs until sometime in the early weeks of 2006, it took me about 4 years to be able to pack the 2.25 inch tube fully. I have now been packing the 2.5 inch tube which is giving me a girth of 8 inches around. I have gained a half an inch of girth in the past year or so. Are these permanent results? The results are progressing through time... but it is just like being able to bench press 20 more pounds and gaining 5 lbs. of muscle... not that permanent if you never step inside of a gym again.
One thing that my cock has experienced is size memory. After my hemmroid experience, I had to get back into pumping slowly over the period of a few weeks, but I was able to achieve my full 2.5 inch packs after that break. Before the break, the best that I ever experienced was a 85 - 90% pack of the 2.5 inch.
Pumping is just like lifting weights... I've said this before. Nobody expects to work out for only a year or two to achieve the perfect body and then stop when you are done and expect for that body to look fit and perfect forever. That is utter nonsense. the same goes for pumping... if you people think that two or three weeks of pumping will get you gains and you can stop without the gains going away, then you obviously don't understand the processes of the human body.
My goal now is to make my erections better by shifting to jelqing and light clamping rather than focusing on more girth gains. Eight inches of girth is enough for almost any woman. I don't think that I will be purchasing a 2.75 inch tube... I will just focus on making my girth the most functional 8 inches of circumference that I can, because at eight inches of girth, I am not penetrating much... I experience the best sex at around 7 inches of girth, I just can't get my stroke right with that much thickness... I am still working like a mad scientist on my penis, my goal is a functional 8 x 8, I have achieved that size, but it isn't very functional at the moment. I need to get in better cardiovascular for my erections to get better, at the same time shifting my focus to hardness and functionality.
First comes size... then you have to work with it to achieve the desired functionality. It all comes in stages and has been a really exciting journey.