Stephen,
By that line of thinking the Taipan 4.9 counts as well as it too was first launched (tried) with a spinnaker although that was quickly dropped after the first races with it. And it is a succesful F16 design although the newer designs are better.
The T4.9 hull is very similar to the Mark 3 and 4 AHPC A-cats. But I wouldn't not call either the T4.9 or T5.7 a dedicated spinnaker boat as the Formula boats and M20 etc are. Back in the days of the T4.9 and T5.7 the spinnaker was very much an after thought without making specific changes to the hull to carry a spinnaker better. Same with respect to the Tornado and Hurricanes. That pretty much changed with the introduction of the F18 class in 1994. From then onwards the spinnaker feature became a integral part of the hull design part. But the designs began really to diverge a little after 2000 as is my original statement.
(To Matt) I'm really at pains to recognize the (strong) similarities between the A2/A3 and the Infusion, apart from both being of the same length.
(To everybody) But I grant that that is a personal opinion.
Wouter
I think look at the under water shape and not the bits above the water. Since the F18 has to take bigger loads and weight, then this shape is different to the A2/A3.
