This has actually been a very thought-provoking topic, and there’s no one like Fantasack for having his thoughts on ball-splitting provoked!
I’m thinking about the possibility that plateaus are reached when the sack and ball support structures develop to the point where they can support the stretching effort without stretching further. Since you’re adding muscle mass and skin area by applying that effort, you’d expect the body to reach such an equilibrium given time. That’s what any training regime will do - any part of the body will develop resistance to any load that’s regularly applied to it.
The logical extension of this is that you might expect to have to keep upping the level of effort to overcome the body’s developed resistance. You can’t keep doing that for ever, so how do you break the cycle?
I think the answer may be twofold. First, I think you need to keep the steady 24/7 stretching effort to a relatively low level (even if you have the development and desire to physically accommodate more weight) so that a great deal of resistance is not built up over time. That will keep things stretching, albeit at a relatively slow pace - any amount of weight will do that. That’s how we no-hangers get to be hangers initially using only a single WMC!
Secondly, you need to periodically increase the level of effort to add extra stretch, but back off before the body has time to build up that extra resistance. In my own case, I’ve always taken fairly regular complete breaks, and it’s worked for me. Makes going back to the weights feel that much better, and hence keeps the thrill fresh every time.
So I’d guess that a regular program of light stretching most of the time (including sleeping) and a higher level of effort for a portion of the time would keep things moving without plateaus intervening. Of course, that takes a lot of will-power because those heavier loads feel sooooo good! Once hung, the temptation to continue becomes hard to resist!
In my case, I’m at a plateau now, but that’s fine because I’m also at the point where I’m not looking for any more significant progress, so a plateau suits me very well! I can keep up my regular heavy-weighting without fear of creating an unwanted extension – in fact, the heavy weight training will discourage any further extension at “normal” loads by maintaining my stretch resistance well above normal loadings. So I may not have to back off the normal loads as much as I had feared in order to hold my ground, as long as I keep up the heavy weighting.
If I wanted to stretch any more, I think I’d have to back right off and more or less start again following a lengthy break to reduce my sack’s present ability to handle serious weight without stretching any more. Not gonna happen – I’m staying right here!! Balls peeping out of my shorts leg is enough stretch for me!