The largest variable factor will always be the nut on the tiller.

After that, in my opinion, the next biggest factor is weight. However, we can assume that, over the next couple of years newer boats will get down to the minimum for class rules.

Thereafter the largest gains have to be in the rig. Reducing windage, weight aloft, better mast profiles etc. We are already borrowing hugely from the sail developments of other classes.

In the short term therefore, the most cost effective gains are undoubtedly to be had in improving our individual performances via time on the water and also by makig our boats more friendly to sail - improving systems so that they are easy to use and effective in all conditions.

just my twopenn'orth...