Of course, the good old back emf.
Good point about the tilt power Kam. Imaging the scenario, you're fishing a mark by drifting over it. You come to start the motor but it fails to start due to the battery switch failing. The boat drifts towards a crab pot and the engine gets caught in the robe. You have no tilt power to lift the engine and cut the robe. Transom gets pulled down and water starts coming aboard.
Think I'll stick with my set up.
BF