It may not be the yokes that are the problem, but that the receiver angle is. Should be absolutely vertical for proper reversing caster action. Otherwise , it can stall in the angle that produces the net vertical receiver angle. Even front to rear angles will/can throw it off. Yes, I know that the blades cut better with a rearward slope, but I'm not bending any yokes on my 4' deck F525, 78" F935, 72" F1435, 84" Woods 7', or my 6' brush cutter, and I jump 6" curbs with them. Sparks but no bends.
I also see a lot of mowers now with cheaper treaded gauge tires. Believe me you want slicks because the 'scrub torque' generated by reversing the caster wheel, is lowest. You want that wheel to swivel as fast as possible (and not tear up the lawn, btw).