Its great for learning how to stop your boat right on the line 45 seconds to the start. In the past i have performed excersizes where you stop your boat then try to get your boat going again and then stop. This way you can learn the time it takes to get the boat moving from a complete stop. Also practice in different wind conditions and wave action.
A really long tiller extension helps a lot. The stern slaps the waves pretty hard.
Note; I am a big fat slob ( Ask Stinky) It certainly is not something you can do when there is much wind. BUT>>> I quickly learned to sail upwind backwards and even to tack.
Locally? We had a backwards race exactly one time wherr we actually strarted and went around an entire triangle. and one of the college kids who was nuts enough to humor me and try it is now 42.
Maybe we need to try again. The other nut still sails. He has a new Laser and is sailing with the wednesday fleet.