I found a great mod for using Dutch's COTPOs. I simply tie a loop of Zing-it onto the white plastic donut. I then attach a mitten hook to my WBBB shelf tie out and connect the two.
Advantage 1: quick attachment.
Advantage 2: keeps line off the ground (no tripping)
Advantage 3: By putting your hand in the shelf and 'flapping' your blackbirds 'wing' you can shake your tarp to clear water/snow or scare off birds/squirrels/neighbors and other undesirables.
As the COTPO is staked on the other side of the tarp using shock cord, there is little or no risk of damage as far as I can see.
Used it on my amazing Ultralight, Gigantic, Low-cost, Yuser-friendly (UGLY) tarp (see UGLY tarp in DIY forum) this morning to do both and it worked great.
Oh yeah, the knots are ugly, but that's part of the charm (bad excuse for spending more time IN my hammock and tarp than working ON my hammock and tarp.