Brian,
I suspect the rig is forgiving enough that effects of minor differences in boom angle on performance might be hard to detect.
I think you’re right about the importance of getting it right to avoid stress on the hardware. I can certainly attest to a scary amount of bend I observed in a stainless fitting holding the turning block at the front end of my boom. It looked like it was there to work around wear in the shackle fastener hole in the original aluminum. (I now have it done with soft lashings, which solves the bend problem.)
I, too, have started to play more with the choker in different wind conditions and seen respectable impact. It illustrates that our boats are very easy to sail, but also very amenable to being sailed better. I personally like that I can have an enjoyable sail when I don’t feel like tweaking, and an enjoyable sail when I do. Like the Almond Joy vs. Mounds ad, sometimes I feel like a nut, sometimes I don’t.
John, there’s some good material at Practical-Sailor.com on Dyneema. UV wear is very sensitive to exposure. Boats in the Netherlands get 3-4 times the life out of dyneema than do boats in the Caribbean. Their current advice seems to be that, because of its strength for its size, you can compensate for the UV issue by going bigger. I.e., if you use at least the same size dyneema as the wire it replaces, that’ll last as long as wire. I understood the article as saying that, assuming ten years of use before replacement, UV will only eventually degrade the dyneema down to the same strength as the wire.
That said, if I was going to go forward with adjustable hanger lift lines, I’d probably want to buy dyneema or spectra with a polyester cover. This would also address the UV issues, and provide a sacrificial layer to warn of chafe.
– Bob