Wouter

I don't favour "eternal chaos in the F16 class". Neither I'm sure does the current Australian F16 champion who has posted an opposing view to yourself on the concept of "over stiffness". I love formula class sailing - that's why I've been sailing and building in it for over 30 years. I wish F16 every success.
However none of the proponents of over stiffness including yourself have defined what you consider is "over stiff" and how that is measured. Of course as platforms are made stiffer in one area failures will occur in other areas. You simply strengthen or change the engineering in that area. Builders and manufacturers do that all the time - even in SMOD classes. You are in a development class so better get used to it. It's called continuous improvement in 90's management speak.
Your measure of stiffness you set out is only valid for platforms of the same weight and length. Anybody with a rudimentary knowledge of engineering will tell you that you can't compare the bow deflection of an A Class with an F18, a Tornado, and an F16. Weight and length have a big influence there. So taking your figures for F16's in isolation, that is a static deflection under only the weight of the boat - not under stress of the rig in sailing conditions. Your extrapolation of times over an hour of sailing is completely erroneous. The differences would be far greater as the deflection is greater under sailing conditions.
I'm sure F16 platforms haven't reached anywhere near over stiffness yet - whatever that is!!!

Cheers