Yes, he says it will rip itself apart if he lets it go.
Seems like what is needed is a good crankshaft, connecting rod assembly and then a way to feed the revolving motor with power. If what ol' McCabe says is true, you should be able to get at least 10 horsepower out of the machine with minimal loading on the two motors.
I still have to ask myself why these things aren't all over the place. Seems rather easy in concept. There has to be a catch. Maybe there is no good way to mechanically harvest the power with the pendulum shaped movement.