I can't imagine why another switch would be needed. Figured the diodes might be for isolation but don't think they'd be needed for this suggestion.
The idea being that to get a start of be off the seat for any reason the cutters must be out and the thing in neutral.
..........and if there was handbrake switch(that might explain the other switch!) that would be in parallel with the neutral and cutter switch. Still can't think why diode isolation would be needed.
