Sorry, maybe I'm stooopid but I don't have to have a magazine anywhere near my M&P with the disconnect to strip it. If I did have to insert the magazine to dry fire the weapon, I think I could be sure the magazine was empty before inserting it in the weapon and then rack the slide a couple times to be sure a round has not mysteriously appeared. For one thing the magazine will hold the action open, and I can easily see the chamber and the magazine verifying there is no round anywhere near the firing pin.

I just completely fail to see how a magazine disconnect is dangerous or trains me to be dangerous. Sorry, just don't see it.