You guys may think I am crazy for saying this, but I think this is a neat idea!
To me, it makes more sense than the Vitality Sensor and the horse saddle since it shows a concept that could well work. Even if EA has done well with Madden on Wii I believe there has yet to be a definitive Wii football game that says "You can't play this on the 360 or PS3!", much less games that use the Wii Remote and Nunchuck effectively.
This shells sounds and looks like it adds more control to the player despite its unusual design. The fact that it even allows for nunchuck and MotionPlus makes me believe they are onto something.
Of course, they need a game in order to seal the deal. Since Nintendo patented it I wouldn't be surprised if they were the ones to make a football game that uses this controller. That or EA, Madden and all that.
So in short, I think it is far more logical than the saddle and Vitality Sensor, but it needs a game to convince people it works.