Despite all previous failed attempts to get a boat with side floats working, this guy managed it.

The critical issue is that the propeller is half out of the water. With one blade pushing on the water and one on the air, it generates a lot of off-axis thrust which (usually) turns the boat into the wall of the track. Furthermore, the half-in / half-out propeller throws a huge spray of water as it chugs down the track. It’s a real crowd pleaser.