I've never been a fan of the mast tip weight rule either. I've always felt that the issue of structural integrity is between the sailor, the builder and the warranty. I wouldn't buy a boat that I felt had a mast that wasn't up to the job.
I'm also not overly concerned about how quickly the rule is introduced. I sail with an alu mast, which I assume is way over the current mast tip limit, and I don't find it puts me at a significant disadvantage against the Stealths, which presumably are a lot closer.
What would you expect manufacturers to do during the transition period? Put some kind of removable weight at the top of the mast? Or build boats that are "obsoleted" within a year or two? (Although as per my previous point, this obsoletion will be more buyers' perception than anything else)
