I think you'll find the mainsheet loads on an A are a little less than most F16's . Also, due to the amount of hours he puts in his hands are probably a lot more accustomed to the abuse and pain. In lighter winds I probably use a similar grip but once on the wire I'm almost constantly applying as much mainsheet pressure as possible hence the need to wrap.
Timbo's suggestion is one which sounds effective as my current mainsheet is 8mm Dyneema with the polyester cover removed where the sheet turns through the blocks. However, I'd end up with red spi and mainsheets which could be a bit confusing when they'd inevitably get tangled. Yes, I could buy a different colour but it certainly wouldn't be as cheap as the red maffioli at my local chandlery.
Rolf, was it you who posted the sketch of a more professional way to grip a sheet?