I don’t hang, but I’m able to reach fatigue using my extender. Based upon my somewhat limited experience, I believe all of my length gains have come from extending while fatigued.
I tried shorter sets for a while and my length progress slowed dramatically. As soon as I started pushing through the fatigue, I started gaining length again.
For me, this is challenging. I try to multitask while in the extender - I’m usually working on my laptop. When fatigue hits around 60-80 minutes into the first set, it’s a somewhat intense sensation. It’s not outright painful, but it’s strong enough to make concentrating very difficult. I generally don’t make it more than 10 minutes in that state, and I get very little done because I can’t focus at all.
Fortunately, I’m able to reach fatigue sooner on each subsequent set - generally in about 40 minutes.
I imagine the hanging is similar only with shorter sets with the ability to reach fatigue much more quickly.