In addition to banning F-Duct, or any systems that uses driver body movements to alter aerodynamics, Formula 1 appears set to... allow drivers to alter aerodynamics - but if they are trailing a car by less than one second. The change is meant to improve passing, but it obviously confers an advantage to trailing cars.
This is likely to lead to grumbling among purists, but one thing that has me scratching my head is the method employed. Electronic systems will enable the activation of the system when a car trailing by the indicated interval. If the driver chooses, he may acivate the system, causing it to adjust the rear wing angle by 10 degrees to reduce drag, giving the car extra speed on a straight. It will be automatically cancelled when the brakes are applied.
This all seems pretty convoluted when you consider that CART accomplished all of this with a single piece of carbon fiber. The Hanford device was an aerodynmic piece fitted to the rear wing of each car. It punched a huge hole in the air - allowing a trailing car that was close enough to slingshot past.
And it worked. The oval races it was used on were fascinating to watch. Well, fascinating in a "What would racing be like if we used this thing" sort of way. After a couple of races where thought "Wow, look at that. It works.", the races became rather silly affairs where drivers didn't want to be in the lead at the start of the last lap,
The Hanford device was not used on road courses, but I imagine a modified version could be made to work. And perhaps a with a more limited effect, it might not be so comical.