Big thumbs up, thanks Sinthome!
-AJ

Here's a highline I set up last year, with an access line in the middle. I used 7/16 HTP and two Omni blocks to tension it. You might be able to see the line if you zoom in (PM me if you want the full file size pic). If the trees are strong enough, like these oaks, I try to have the line tight so I don't have to fight going up each side.

I could have used such a setup today. Was cleaning gutters on a 3-story house with a roof pitch of about 14/12. I could not reach a couple of the high ones. There were several tall fir trees that I could easily anchor to and string a highline.