Please note that while there have been some "major" changes/upgrades to the H16 over the years (IMHO), most notable the re-designed front crossbar, the IHCA still claims it is operating a "One-Design" class. This is a "pet peeve" of mine as the TheMightyHobie18 and H17 have basically had no changes/upgrades since the day those models where first produced.
Harry
By redesign of the front crossbar, I assume you're refering to the integrated traveler tracks. Hobie did the exact same thing with the 17 rear cross bar (and later front cross bar) by integrating those tracks. The 18 already has an integrated traveller track.
And each of the Hobies you mention (16, 17, & 18) have gone through changes to their respective hull lay-ups which have significantly altered the overall boat weights (either increase or decrease). Additionally, they have ALL had changes (minor & major) to the sail cuts since being introduced. So really, all of the boats have had major and minor changes throughout their 25 to 35 year existance...it's not just the 16.
Sorry to drag the thread so far off topic.
sm