On the original subject of the HH, I wish one of the vendors that sells HH's would prefab a compact stiffish loop (for advancement while ascending) to sell along with the HH itself.
I have built some diy versions with wire, cord, etc, but to be honest if someone sold a simple version (compact,that would stay in place) for a reasonable price, I'd go that route.
Maybe just a simple stiff cord loop with sewn "eyes". Not life support so can be minimal.
I don't mind splicing my ropes, slings, etc, but with free time so short I would rather not mess around with recreating the wheel for that one unsophisticated application. And production would be far simpler for someone building a bunch of them.
Too many things I am already not getting to. And on top of that I manage to drop (and lose) my favorite wire loop at 200ft above the forest floor recently. I don't want to admit how much time I had into bending the stiffish wire to the shape I wanted....
Note: I do not feel the same way about working on ones own friciton savers, RW stiffies, etc. These sort of things are highly personal and esp when no commercial product suits one's needs, it is well spent time to create one's own.