Id be more worried about your rear cog unscrewing, if you use left side of the flip the cog is effectively backwards, so when you pedal forward you'd be unscrewing the cog!
I guess with some red loctite and a big ass chain whip you might be ok..

As well, I've heard you can drill out the pedal threads on teh left-hand crank and install a left-hand helicoil to get the proper pedal threading, though im not sure its worth it.