I do like the concept of the U-turn, but like the FF, it has to appear more frequently to have any sense of strategy, and the two tasks should be located near each other.
I personally think that Joe and Heidi had ample amounts of time to solve that Morse Code and beat Jeff and Jordan. It was only 25 characters, and they had the translation book. They just didn't tackle it methodically because being U-turned messed with their minds. My issue with that leg was there was only one major task, and there was pretty much no way to recover.
In classic TAR, the producers would have made the teams go on an epic 500 km+ drive from Hamburg to France, not use some mobile pitstop as a cheap way out. That alone would have made the episode more fun to watch.
The express pass will be a physical item that allows a team to bypass any one task up to a certain point in the race (Leg 8 maybe?).