That was a lot of rigging, more than I like to do. I pull my tarp ridgeline pretty taut too, but mine, like most of ours is just a separate line on each end of the tarp. I found that using Ed Speer's multi-wrap knot finished with a slippery half-hitch or something like that allows me to pull taut with mechanical advantage and wrap/tie the knot under tension. I think the mechanical advantage I get is that the line starts on a tangent to the tree and the wrap cinches it to the center of the tree-- anyhow, it works well for me and doesn't require tying/untying an extra loop in my ridgeline. I do have to work with the multi-wraps, although I just do that on one side. The first ridgeline I just use a slippery bow line knot which is very quick and easy.