I have seen tarps run with ropes on either end that connect individually to the tarp or a continuous rope running under the whole tarp.

What are the benefits of running a continuous tarp ridgeline? Will I harm my tarp (Wilderness Logics Big Daddy) by only tying off ropes to each side to connect to the trees?

In case I want to run a continuous, I have 25' of amsteel coming, is that going to be too little?