I bought a 2016 Shelby GT350 last summer. My oil pump died (OPG shattered) around 7,000 rpm while doing a WOT pull (8250 rpm redline). I quickly put the clutch in and took the car out of gear, and was trying to kill the engine via the start/stop button while rolling/braking to a stop at a safe place on the side of the road. I was unable to turn the car off until I came to a complete stop. It could've been useful had I known on that particular platform you have to hold the button in for a few seconds to kill the engine. I kept pressing it over and over, with clutch in (in neutral) and with clutch out (in neutral), but I never tried just holding it.
In my case, it didn't matter much as the engine was replaced under warranty, but it could've mattered if I were rebuilding the engine myself.