I guess oval chain rings are a load of nonsense and don’t really work. I have some Rotor Q-Rings.

Froome Used this in his 2015 TdF victory.

http://cdn.mos.bikeradar.imdserve.com/images/news/2015/07/10/1436523606273-xzs6zx1dsaig-700-80.jpg

Wiggins used these for gold at the Olympic TT

http://i1171.photobucket.com/albums/r554/bikelife/bradley-wiggins-canvas-size-1-942×707.jpg

Must be a placebo effect?