The Tornado Class has been around for 40 years and has been in the Olympics for 30 years, and now all of a sudden they need a minimum crew weight limit?
What's next -- a maximum weight limit when they are going to sail the Olympics in an area where it blows 25 every day, with big seas, in a country where the people are big?
How do you do corrector UNweights?
To a point, even in windy conditions, I'd still prefer to have less weight on board than more. What that means is even in windy conditions VMG downwind is at worst unchanged and often slightly better than the fatter teams.
Something that is different now to 40, 30, 20 or even 10 years ago is the state of rig tune & sail design. Both have come a very long way and the sail/mast combos give very efficient sails with minimal drag for up wind sailing which once again will diminish any (small) advantage the heavier teams might have on this point of sailing.
Tiger Mike