I don't see how this could safely work with randomly grouped trucks. Different trucks, different aerodynamics, different weights, different brakes, different road conditions between the lead truck and the tail end, etc. Even trucks spec'd the same from the same company are going to vary.
Mr. and Mrs. John Q. Public and all the little Publics don't like sharing the road now with big trucks. Wait until this becomes popular. If trucking companies want to save put the trailers on a choo-choo train. The U.S. is supposed to have the most efficient rail system in the world for transporting freight. Not so for people.