2ndplace

@MrDuck: Of course there would have to be a frame built to accommodate a floating chainring [RH side of the bottom bracket and chain stay modified, also a special crank with splines for a chainring hub to float on],definitely doable, any prototyping department of a bike manufacturer could do it. If a manufacturer did this, they would have a significant selling point that would stand out from all the other bike companies.

One more addition to the Rear Derailleur system to reduce friction due to chain misalignment is to have a floating front chainring [single ring], having it float the full width of the rear cluster would be hard but I can see floating half the width. A floating chainring will tend to "self align" I am surprised it never has been tried out, floating pulleys/sprockets are used in many applications to stay in perfect alignment.