... Yeah, it's kinda pointless to drop another $400 on a card when the new series is just around the corner.
That being said, does "optimal settings" mean maxxing out the game? You have to turn a few things down with Crysis 2, but it doesn't make a visual impact whatsoever. If your source told you you wouldn't be able to run at, say, high settings, then they're simply wrong - you can run at mostly ultra.
As for Battlefield 4, it's a long way in the future, AND has traditionally been a CPU-bound game anyways.
However, it sounds like what you're doing is trying to rationalize the purchase. If you want to get another 670, then just do so, instead of looking for an excuse. (You don't have to buy another of the exact same sort of 670, by the way - an MSI lightning would SLI with your EVGA FTW just fine. Wasn't sure if you knew that.)