Seriously, even if it's true, which it's probably not due to the amount of credit you'd have to give Bioware (the the amount of forgiveness you'd have to give them for not including a pretty important story element), it's still shoddy writing because nothing we did matters. At all.
On the contrary - it returns meaning to the 60 hours of gameplay that the ending that we currently have renders moot.
Only the very final section of the game is a dream, when Shepard is drawn up into the Citadel. And the theory is only valid if fulfilled with a true ending. Saying "it was just a dream!" is not a better way to view the crap we were given; it's a hope for a proper ending that follows on from what we have. It's more of a prediction than simply an alternative interpretation as it stands.
Some people think the current ending is exactly as it appears, and any extra content will build on the destroyed relays and synthesis/control idea; others believe choosing to destroy the reapers represents more than the current ending presents at face value, and will be a springboard to an ending in which we don't have to fuck up the galaxy to stop the invaders.