It’s just opinion. I think there are 2 different things. When person see edema, then it’s not gains, but fluids building up. That probably leads to situation why people see gains and think it’s temporary. But in reality it’s more like injury, which of course is healed soon. For proper gains we need to stretch tissue and here is why pumping can work for one, but not for another person. If routine gives such expansion, then it might work. If not, then another way of force applying needed. It’s quite speculation, but I’ve noticed for fast and stable gains, expansion must be 1/2 inch or more. When we talk about some small difference like 1/8 inch, then it’s close to natural size change. When I push kegel, I get near that girth increase and I haven’t noticed significant girth gains with such exercise besides erection difference. So I suppose anything lower than that at best can give small gains in very long time (1+ year) or none at all. We probably need at least 1/4 inch expansion for that. And when people see huge expansion like 3/4 or even 1 inch difference, then it gives extremely fast results. But again, I talk about tissue stretching, not edema.
For example, I have quite some pubic fat and thick pump’s cap, so when I loosely start with it, I fill only around 7 1/8 length. But during pumping session, I start to push 8 1/8 ceiling of pump. Part of that comes from pubic fat, so I would say it’s around 1/2 inch difference. If I do pumping for significant time, not only I push ceiling, but half of my glans is completely pressed and distorted by it, so it’s even more. And I see very fast gains from that. It’s visible in weeks, not even months. But at the same time, I don’t see much of girth expansion, so I mostly need to do other exercises for that.
Starting : 7.6 BPEL, 5.5 MEG
Current: 8.1 BPEL, 5.7 MEG
Goal: To understand what makes penis to grow.