We're getting close.
I think the point here was that the guy possibly wasn't specifically trained to confirm the engines were shut down by checking NH was zero. Assuming that he knew and understood not to move the condition levers out of fuel off until the engine had shut down, it seems to me that he thought the engine was in fact shut down. The reason he moved the levers out of fuel off was in an attempt to diagnose a possible rigging issue, something even an idiot wouldn't do if they thought the engine was still running.
So then the question becomes: why did he believe the engine had completed the shutdown sequence? What cues was he trained to use? Do dash 8 pilots monitor the engines until NH reaches zero, and then verbalise this? How long does it take for the NH to reach zero? I'm not advocating this as a method, just wondering what happens. Maybe some other dash drivers might like to comment.
Touche re the good ol' Garrett.
