I doubt that if anyone will ever break the sound barrier with a boat!Ken Warby did his thing 20 years ago and he may beat his own record by another 50-70 mph,far from the speed of sound.Ther was only one guy [Lee Mizer from Florida] who built a craft called Mizer Hydro,that he built with aircraft like controls [joystick vs wheel]and it was powered by a rocket engine rather than a jet.It had a theoretical speed of 500 MPH.The boat practically was an airplane not a boat,and I don't think it worked out well.Lee Taylor died trying to beat Warby's record [he did it on the unofficial run] on the official run doing 315 or 335 MPH.It will be a very tall effort for Breedlove to even catch up with Andy Green.