I've slept a lot of nights in my HH Expedition, and I must admit never once tried to regulate the tightness of the ridgeline. Perhaps I should. The only thing I ever checked was to make sure it wasn't loose when laying in it. The HH ridgeline is fixed to give you their patented "perfect hang" every time.
I don't think it's possible to hang your Hennessy in a way that will put your full weight onto the tarp ridgeline causing it to snap. This is two years of hammocking ignorance talking here. I've hung from trees 25 ft. apart (I have long whoopies and tree straps). If that didn't snap the hammock ridgeline nothing will!
When I replaced the HH rope suspension with whoopies, I thought about adding an adjustable Zing-It ridgeline. However, I read too many posts that said, "you don't wanna mess with the Hennessy ridgeline. It's part of the design." So I didn't mess with it.