I will definitely have a separate tarp ridgeline, 2.2 mm Zing-It with knotbones and Figure 9s, using 1.75 mm soft shackle prusiks to attach tarp & Figure 9 to ridgeline. One of these days I'm gonna convert my Hennessy Expedition to whoopies with a separate tarp ridgeline, but that's another project.
I think I'll take your advice and skip the overlap on the ridgeline. From what I have read, the Tyvek would probably wear out before the tape. Don't know if you've ever handled Tyvek tape, but it is nothing to mess with. Once you tape something it is darn near impossible to get off.
I thought about grizz beaks, but I like integrated doors. If this tarp doesn't suit my needs for hammock camping, I can always use it as a group/cooking shelter. And if I don't like it for that purpose, I can always just cut it up for other projects. I wish I had more Tyvek, 'cause I'd like to try it out as a hammock overcover or undercover for winter.
Thanks for some actual input on the question at hand. I was beginning to think the thread was going to turn into a David Letterman "Top Ten Reasons Why Tyvek Is Like Paper" thread. If it did go that way, I would want Rick Perry to present the Top Ten:
10. Tyvek is white, just like most paper.
9. Tyvek is flat.
8. Tyvek can be cut with scissors.
7. I forget the other seven reasons why Tyvek is like paper. Oops!
Thanks again for the input!