Jeez, Steve - who pissed in your cereal? BTW, there is no carbon in the 16, except for aftermarket rudders.

To answer the original question:

In 1983, for the 1984 model year (before the H-16 became an ISAF International Class), Hobie Cat changed the hull contruction method, laminate schedule and hull/deck glue. The result was a 20 lb weight savings - mostly in resin. As any boatbuilder will tell you resin=$$$. They were making the boat cheaper to build while maintaining the strength.

The minimum weight hasn't changed in 23 years.

Steve's right in one respect - you would have a tough time doing well on a 27 year old boat in a Hobie 16 North Americans. You could put all the minor upgrades that have occurred in that time - rudders (which have always been open - you should see some of the beautiful wood rudders the Brazilians make), travellers (both main and jib), etc., etc., but you can't put a 16 on a diet to lose the 20+ lbs.

In addition, old boats get heavier over time as they soak up water.

On the other hand, I've qualified for the last 3 H-16 worlds on a 1998 platform. (In 2004, I broke down and bought new sails for it - everything else is original.)

There are very minor differences between the boats built in the US/Australia vs. the boats built in France. Mostly hardware. (For example - HC USA uses different port/starboard upper rudder castings and straight tiller arms. HCE uses identical upper rudder castings and bent tiller arms. Does this make a speed difference? I don't think so.)

As for the sails, they are theoretically cut from the same patterns. I'm sure there are minor differences, but to say that the provided boats at the SA Worlds suffered from "a lack of power" is just whining. Especially when the conditions were like this most of the time: