I agree 110% TOM, every one of the examples given here as a reason for using an ignition kill switch was caused by poor set up, maintenance, or preflight practices and avoidable. Personally I don't have a strong feeling either way about them, I have a couple planes that use them and several that don't, all will shut down with throttle kill or they don't leave the shop, PERIOD. The other major issue I see represented here is the ridiculous decision making that occurs when a something does prevent a plane from shutting down. There is no plane or propeller worth even someone else's finger, hand, or any other body part let alone my own. There is absolutely no intelligent reason for anyone to try and catch a running moving airplane unless it's to prevent it from hitting another modeler. If one doesn't have patience to wait for the engine to run out of fuel or the air speed to fly while doing so a well timed application of down elevator should solve the problem right quick.

All that said, the lack of knowledge and experience in many of todays gas engine users coupled with the need of many to plug and play, rushing through assembly and heading to the field without checking and double checking every component knowing with 100% certainty how everything works or even whether it works or not makes me believe that ignition kills are a good idea. Not because the engines or planes are so inherently dangerous but because modelers are evolving, many are using OJT principles to learn about and how to use new propulsion systems with larger engines and planes. With this method of education it many times requires a mistake be made in order to learn something.