In the Venice Raid we used many close encounters to experiment with our weight- and sailtrim. We realised that the boat goes that bit better when -sailing close winded- you grab the mainsheet as a whole and pull it to windward. When doing that, the boat sails higher and at the same time the weather helm eases noticeably.

So the next thing we will introduce to the boat is a simple temporary traveller functionality for the mainsheet. I am thinking of a temporary rope rig to haul and cleat the mainsheet bundle to windward on occasion. Fastening point can be the horizontal gunnel area between jib and mizzen cleats.

Hi, Claus.
Ive notice a similar thing on Four Sisters balanced lug sail. After heaving to, (main free, mizzen in hard) Im in the habit of freeing off the mizzen and holding the end of the boom out to windward to push the head around on to the chosen tack. Hang on to it for a while - only possible in light airs - and shes off like a greyhound. Let go too soon and she wallows around until the main sheet is pulled in hard. Something to do with the sail twist between boom and yard, I think. I have the luxury of a mainsheet track on the cabin top, of course, but can only really use it to good effect if I have crew willing to put their book down and cooperate! I can\\\\\\\\\\\\\\\'t reach the jam cleats very easily from the tiller - yet another modification I need to work out, and more sailing time lost while I muck about with the Makita.
A friend uses a system like the one you suggest. He uses a butchers hook slipped over the boom and fixed to his rowlock with a loop of doubled up shockcord. Crude, but he claims an extra knot on a fine reach.