Hi David,
Did you know that there is a presently manufactured boat that is faster than the D class boats and costs about half as much? It also has real and substantiated PNs. The boat has been around since the early 1980s. This boat is smaller than the D class boats and much lighter in weight and it doesn't require a crane to step the mast.
This boat was around during the F40 days. It is rated faster and cost 1/10th as much as the F40. Professional sailing would very likely be alive and well today if this boat had been chosen as the vehicle for competition.
Good Sailing,
Bill