Let's tackle two fronts. Our brother
@9.5inchpro may be in the same predicament as you are, where both of you are hitting a hard limit plateau. I've posted a discussion about this after talking to my colleagues on his log page:
Okay. This is what we've suspected as we discussed based on your posts so far. So, take it with grains of salt when you're reading these recommendation from us.
First off, we always talked about thermal application at body core temperature. However, because your tissues are so dense now, your collagen type I (the stiffer type) is higher than the collagen type III (more elastic). This is why you're not breaking. So all of us express thermal incline from core temp to as high as 110F. It's going to be quite warm. Go higher if you are comfortable and it doesn't cause heat irritation or...
We can go into greater detail where you find a bit of info-lacking.
As for the buffer space, there are three parts to this. First is the buffer space around the penis, that means the spacing between the shaft and the
cylinder's wall. Without the extra space around it, the negative pressure cannot pull the internal soft tissues apart to break through the cross-linked or toughened fibrous meshes that are your tunica and septum that make up the blood chambers. The same is true for the head buffer space. If you're only having 0.5in of head buffer space, there's a lack of pressure air volume, or even fluid volume, to pull against your penile structure. Think of the air vacuum volume like an invisible hand that's pulling on your penis. The smaller volume of air slightly around the penile shaft and a larger buffer volume at the top create less pull than the larger volume around the penis and larger head buffer space. The trick is find a balancing air ratio between the penile shaft to the
cylinder wall vs the volume buffer space between the top of the glans to the top of the
cylinder wall. The ratio should be around 1 to 3.5 or more. Make sure to always pump at the highest erection possible, and keep the erection going.
Second to buffer around it is heat. Heat plays a very critical role in making the tissue layers pliable and malleable. Without heat, the tissues remain cool and dense without proper expansion.
Third is the weakening of the tissues. You already know the game long enough where you have to soften the tissues before lengthening and expanding. Otherwise, you're trying to expand cool and thick tissue walls. The best comparison to this is trying to inflate a hard, thick inner tube rather than a stretched and loose balloon.
Those who are engineers and fluid mechanic specialists will be hammering on this subject.