Personally I think that a given build adheres to a specific class that it should adhere to that class rating. Ergo a Taipan 4.9 with spi must sail of the F16 rating, the BIM A-cat El-Cheapo races off the A-cat rating and any F18 foundation boat races of the current F18 rating.
Otherwise any of these boats should form their own SEPERATE class under a different namen and acquire their own seperate rating.
Wouter
While I agree with that, the sad reality is that with the performance and statistic driven USDPN handicap system, if the boats are slower around the course (and they show up in numbers), the new boat will have the effect of increasing the rating of the existing fleet of a-cats. In a fleet of apples, it would be an orange and the handicap system would need to make an accommodation for it. Otherwise, the current fleet of 165 lb a-cat ratings would go up making it unfair for anyone that races against them in the future.
