OK, here's the compromise:
BAN ALL BOATS (the first time I've used "ban", incidentally

) whose
insurance premiums for civil liability would exceed the dollar-settlement paid out in Littlefield's Lake Winnipesaukee "incident".
We can use Lloyd's of London low rates (they have lots of co-insurers) for a standard comprehensive premium rate chart.
It would be easy to determine for the boat owner...and also easy for the MPs in their determinations.
Codeman671 started this thread looking for a compromise: this one's issue-neutral!
What say
you?