Bob :
Thanks for putting me straight without making me feel like an idiot, I can do that all by myself. Good to see you`re so passionate about the boat you own, and came to Bill`s defence so quickly. Just to note : I was not trying to discredit Bill, his designs or his sailing ability in my post, was just trying to make a comparison between a "heavy" boat & a " light" one, & was taking info from a race report which was incorrect. (unless you guys always double trap in a "drifter", if so I`d hate to see it when it`s "howling" in your neck of the woods !)
Again, that`s why I did the comparison between my boat (Mozzie)& Taipan. Although they weigh the same, the Taipan`s tall rig makes them quite a lot faster up to 15-18 knots, but when they start backing off we can still push hard, so the difference in speed is less. My whole argument hinges on the following understanding, which might be mine alone : The lighter the boat, the less sail area it needs to go as fast as an EQUAL DESIGN heavy boat. Now, the less sail area it has, the more prone it should be to being happy in strong wind. Simple. (or not, depending on your opinion).
If you`re looking at different design or length boats, it becomes totally subjective & is impossible to come to any conclusions. That`s why I put the question out as to whether a standard rig SC20 down to it`s design weight might not have been faster on the day. Not a question I need an answer to, just illustrating my point. Come to your own conclusions.

So now that leaves me with Bill :
Apology for drawing my own conclusions from the race report, won`t do it again.
One theory states that with one less rudder, you had less drag & so must have been faster ! (Ask H16 sailors why they pull up one rudder downwind.) Don`t take offence, just my sense of humour getting me into trouble again.
Again, I was under the impression from your many posts that the SC range was built out of low-tech materials & methods to keep costs down. Now, In SA we understand low tech materials to be chop-strand mat with polyester resin, which is how the Dart 18 is built. What we understand to be "high-tech" is vacuum bagged epoxy foam sandwich, with a LITTLE bit of kevlar or carbon thrown in for reinforcement, which is how the Mosquito is built. Dart hulls weigh 48kg each, Mosquito hulls weigh 22kg each (and plywood hulls are 18-20kg, so one could deduce that plywood is the most high-tech of them all !) Knowing the Auzzies their boats are even lighter. So once again I was drawing my own conclusions based on my own understanding, something I`ll be more careful of in future.

And now onto the ARC 21 vs Inter 20 comparison :
"ARC 21 @21’-6” weighs 400 lb, 33’ mast, 282 sq/ft main/jib, 346 sq/ft spinnaker.
I-20 @20’-0” weighs 390 lb, 32’ mast, 246 sq/ft main/jib, 270 sq/ft spinnaker.
The ARC 21 is 1’-6” longer, a foot taller mast, 36 sq/ft more in Main/Jib, 76 sq/ft larger spinnaker…yet is only 10 lbs (doubt if the sails are included in either boats weight) more than your “lighter” I-20. Plus the ARC is Epoxy/foam sandwich, and the I-20 uses Vinyl ester resin/foam sandwich (not as strong). "
Thanks for that, Bob, how do I get my hands on one ?.

Bill, you still need to convince me that a 17ft boat with more sail area than a F18 can be sold as a beginner`s boat !

Cheers
Steve