As I have shared with you in the past, please remember I do not speak Her Majesty's English. I speak Bad English and Redneck (with Redneck being one level under Bad English). I never said rubber band. I said Elastic Band. In Bad English we call it a Thingy. In Red Neck we call it a Doolie Whopper. As such, here is our setup...
This is basically two separate lines. One has the Chain hook on the bitter end, a rubber snubber between, then leaves open the loop. On the loop, slightly off center (explain in a moment), is a second line with loop and bitter end.
Why is it off center? Good question (and no, alcohol was not involved, well, it might have been, but that's not the point). Ever get a current running one way and the wind another? Sometimes it makes the boat sit funny. So I use this to try and kick the boat over slightly to one side or the other. It works 'ok', not great, because my cleats are so far forward, but I suspect that if I was really interested, I could run a leader off of one side to midships to present a different angle. Generally too much trouble for me.
To hold on the hook, I use a Doolie Whopper (illustrated below).
Note, some people call this a Watcha-ma-callit. That is incorrect. It is, in fact, a Doolie-Whopper (technical term). This is nice because it keeps the hook on the chain, but gives a bit without snapping when pressure is put on. As you can see, both of these have spent a lot of time under water! However, in a pinch, this comes off very easy.
Y'all let me know if ya have any questions.