Performance step changes.

Those bits the Moth class stuck on the bottom of there foils seam to have been a bit of a step change that has been brilliant to watch. So there is at least one good development since the 70s I think. 

Originally posted by iGRF Nope, the only serious performance step change was the articulated mast foot joint that gave rise to the biggest increase in independant performance sailing.

Which in turn was enabled by the wet suit. Board sailing in 1930s dinghy sailing clothing would leave a lot to be desired!

Windsurfers brilliant, enabling use of wind from anywhere and could be carried in a van or roof of a car, then carried by hand, much like sit on top kayaks, 'Topper' probably nearest dinghy to meet this convenience.

Oddly I think both trapeze and sliding seat may predate toe straps. Sliding sets date back to the end of the 19thC. What we would call trapezes were in use on Malaysian racing canoes about the same time. Its uncertain whether they inspired the european introduction, but they were reported in western yachting media, so its certainly possible.

Sailed on Strangford Loch in Northern Ireland  in an old traditional class - think they were called "Rivers".  No kicker so crew would sit on boom to keep it from lifting up and depowering main.  If wind got up crew were lifted  up feet off the deck, add another crew member - downwind  these  crews members needed  confidence that helm would not allow a crash gybe.  Lovely boats to sail.