Yes, it's very helpful to bag the sail for the downwind speed run and then flatten it for the upwind. I have run adjustment on only one side for years at Sandy Point for simplicity, but this year I added adjustment to the other side of one boom, as I found it very usedful at Lake George, where I didn't always know which tack I would be doing speed runs on.

The Formula and Raceboard racers sometimes have quite elaborate continuous chord around the mast and lots of thin bungie chord to keep everything in reach and from swinging and dangling, but that stuff is not realy nessasary for GPS stuff. IMHO, keep it simple is best.