That's one thing I like about the hennessey hex tarps. They have the pockets on your tie out edges. Makes it nice to roll and tuck your guidelines in to. The tarp I am using now does not have them, so I wind the guidelines around my hand then take the last six to eight inches and roll that around the winding. That way I don't have a stringy mess to pack up.
So I like pockets on the corners. It's a good thing!