Decks, Patios, Porches and Docks - weathered Decking

This may seem like a dumb question but here it is anyways. I built a deck two years ago and due to cicumstances beyond my control I was away from the house for two years. As a result it was never treated and has weathered badly with splits, cupping,etc. The under part of the deck is in good shape as it was made with pressure treated wood. What I would like to know is can I unscrew the deck boards ,flip them over, and rescrew them to the joist. The bottom of the decking looks brand new. By the way this was that so called "sun wood" and even though it was not treated after installation, it looks like total garbage after two years. I feel like the guy on the Thompson commercial.

Yes, you can flip the over. There will probably be a couple that will need replacing. Another good reason not to use sunwood. Good Luck