I don't agree with you on that one Dazz.
As the organisor of this regatta, a competitor in the event and an A sailor for the last 30 years I've seen plenty of changes with more impact than what we saw in the last week.
The move to wing masts and composite hulls in the early 80's, flat top sails in the late 80's,carbon masts in the early 90's and wave piercing hulls and high profile foils in the late 90's all were very significant steps forward. Through all these eras I've always been able to sell my old boats for good value. There are always people wanting to get in to the class with boats that are well set up and maintained. The class is already the largest OTB cat class in AUS and has very strong numbers in Europe. The US is seeing strong growth and will only get better as their sailors compete overseas more. Hosting the 2012 Worlds will also be a boost.
Of course a development class will see change, but the redundancy factor doesn't seem to restrict interest. The top sailors seem to use new boats in the limited or one design classes too when they compete at the highest level. I don't think world class sailors would use 5 or 10 year old boats in a Hobie 16 event or a Capricorn in a F18 Worlds if a C2 was available. Are they redundant - maybe by your definition, but still very attractive to the mid fleet sailor. I felt very comfortable on my Geltek II with canted straight boards in the event. I sailed next to DNA's many times and didn't feel outclassed. It's just incremental improvement.

Cheers
John Dowling