How to better tighten a snow chain

Due to the shape and profile of the Heidenau K60 tire, you won't get a tight fit when only put tension on the chain at a single point; a rope, splitting tension over the whole chain, gives a much tighter fit. Optimum would be a nylon string with build-in hooks. My knots are temporary and would collide with braking cables, so consider this picture a basic example. No warranties, and I did not yet try it on the bike...