Well, I mentioned that in one of my previous posts. I would make 3.17 much more relevant, saying that a point load of X Newtons can be applied in any point within a defined zone, with the force being roughly equivalent to what would be seen at 300 km/h. The zone would effectively encompass the entire main-plane of the wing and the endplate (including the step).
Assumption time:
1) At 300 km/h, the front wing makes roughly 4000 N of downforce (total guess).
2) At 300 km/h, most wings only deflect 10 mm.
*These would change to reflect more applicable, current data, if given the resources that the FIA would have.
3.17.1 (Malcolm's Version): Bodywork may deflect no more than 10 mm vertically when a 4000N load is applied vertically to it anywhere within an area bounded by four horizontal lines. One 1000 mm forward of the front wheel centre line, one 500 mm forward of the front wheel centre line, one 500 mm from the car centre line, and one 895 mm from the car centre line. The load will be applied in a downward direction using a 50 mm diameter ram to the centre of area of an adapter measuring 300 mm x 150 mm, the 300 mm length having been positioned parallel to the car centre line. Teams must supply the adapter when such a test is deemed necessary.
That's how I'd write it, though I would alter a few details, such as the testing zone, forces and flexibility limits to accurately replicate on-track forces seen by the wing. I would want to test in a range of areas to ensure they are not using an offset centre of pressure from the testing point to allow the wing to twist forward, allowing it to flex in a different manner than that which is currently tested.
Why aren't they doing that? Who knows...? Ferrari and McLaren weren't happy that they have to develop more flexible wings when a rule states that wings shouldn't flex. Rather than the limit merely being a limit, now the limit is becoming a target, as teams are ignoring the fundamental rule that states wings should not flex.
The FIA have seen the effects of wing failures, and by having teams developing flexi-wings, I am sure we'll see some failures in the future (Vettel at Silverstone won't likely be the last, especially if HRT tries to make a flexi-wing!).
Perhaps they believe that a front-wing failure is less dangerous than a rear-wing failure, and that perhaps advanced flexible composite designs could be advantageous in other industries (aerospace, etc), and by allowing teams to do this now, it could position them at the forefront of such technologies if other companies want to design such features into their products (aircraft, road cars, trains, etc). This could help teams become multifaceted (like Williams, with their hybrid technology), and secure their financial side for years to come.
Ok, enough talking out of my... err... postulating.
However, 3.15 still states that wings shouldn't flex, and teams now have to design wings that flex. It's dead easy to make very rigid wings that barely flex at all at 350+ km/h, but now have to make wings that flex almost 20 mm at 1000 N, but far more when going 240 km/h, but not flexing too much as to scrape the ground at 300 km/h. How does that make sense?
If the FIA wants flexible wings, they should remove 3.15. If they don't want them, they should enforce 3.15 better by improving 3.17.
It's that simple.