In turbine engines when a power turbine or gas producer turbine speed is exceeded mechanical inspections are required to determnine if the centrifical force has caused cracks in the turbine blade or caused a blade to contact the engine housing.
I've also seen rods thrown in 2 and 4 cycle engines caused from old exsessivly worn engines combined with high RPM. High RPM can also cause valves to float or not fully close, but I'n not much of an expert. Sounds like Texan knows alot about it.