I've thought about this idea when looking at my spinner. I think that it would work on a larger bag that you would check anyway. One with bigger, smoother wheels like my old Pathfinder. I'd go for two wheels folding up into the chassis and the other two retracting to serve as the two rolling wheels.
I'd like a suitably Victorian, imperturbable mechanism that uses a hex key to crank the wheels in and out, but I know everyone else would want a minimalist aluminum slidy thing.