If it connected to both the coach and he toad in two places, it would force the toad to either steer or scrub tires. I can imagine where turning the coach could force the toad's steering back toward center after caster had tried to take it to the stops on one side.
I think doing that, and accomplishing a turn like the 90-deg corner mentioned above, would take a lot of skill on the coach driver's part plus a very good spotter looking at the toad's wheels.
Sounds like something a skilled demonstrator could pull off at a show, but that the average RVer would be unlikely to be able to duplicate.