Come to think of it, IF the ridge is only inflated AT speed, and 'instantly' deflated on braking, the additional tread wear might be negligible, though turning would tend to eat it up. The 'dump' valve(s) could readily be tuned to support 1/4 of the car's rated loaded weight at rest (or at speed), and any higher pressure/load would dump the pressure and prevent it from inflating. Braking and accelerating would dump it. Hard turning would dump it. Overloading would dump it. Potholes or bumpy terrain would dump it. Another tire going flat (or dropping off its middle) would probably dump it, too. So then the bladder would be inflated from the tire's own air, and only if the amount of weight/stress on the tire is small. The air channels can be formed on the rim, where the bead of the tire meets metal. So one channel could be inflating the tire, and one channel can be inflating (or attempting to inflate) the center. No brains needed at all for the center bladder, and inherently as safe from leaks as the tire is without it.