That works for me.

I've lived with myself long enough to know that, no matter how well marked, no matter how difficult I make it to plug a battery in backwards, it's just a matter of time before I do it anyway. And if I make it IMPOSSIBLE to plug in backwards, then... it will only take a little longer to do so.

I'm ashamed to admit how much time I've wasted trying to plug the Dean's connectors in backwards before realizing they only fit together the other way! Then I curse myself for being dumb, and thank the Dean's company that they just saved me another $100.