Yes, the difference between that option (the more southern red branch on the map) and a western bypass is only the future traffic to Grenoble, Savoy and Italy. The Mâcon option would separate only the Rhin-Rhône and Haut-Bugey bound traffic, but all the rest of the southeast TGV traffic would use the short section until the start of the Lyon eastern bypass.

_{*Lunatic*, n.
One whose delusions are out of fashion.}