Have also seen the result from a 'crash engaged' starter motor, not pretty, wind and disengaged clutch pawl springs do not mix!
Have known guys whilst ground running to throttle the engine up slightly to blow out a tail pipe fire, as per their ground run manual.
I remember meeting an aircraft with no apu available, guy shutdown both engines simultaneously, a tail pipe fire occured and we had no way of blowing it out quickly, luckily found an extinguisher!
