for someone to improve on a simple idea but I think you might have done it. I use this method with my asymmetrical spinnaker block to keep it from banging around on my teak bow pulpit. I run shock cord inside of nylon tube strap up from the block to the bow pulpit to hold the block up. Your idea is kind of the same thing but using poly rope and 40 feet of it instead 3 feet of nylon strap. I totally get it. The only down side I see is that it might take up a little more room. That would be offset by the ability to coil it up and more sun protection. I like it.