"Brigham Young is not going to the Big12 until it does." If you're looking for a reference for that quote, you'll find it next to where Homer Simpson quoted Abraham Lincoln about the Internet being on computers, finally.
However, the fake Yogi Berra quote does make a great deal of sense. A deal isn't done until it is. Actually, I like looking at it this way, "A deal isn't done until I can buy a beer with the money." Of course, my beers are heavy on the root.
The point is, our beloved and cleverly curated Cougarboard, Twitter, and the FWIW crowd with all of their "sources" don't know anything until Tom Holmoe is standing next to Bob Bowlsby and shaking hands.
So, in this case maybe the saying should go something like this: "BYU is not in the Big12 until I can make fun of a guy with a royal blue and white Big12 decal next to his old school scooping cougar BYU decal on his beige 2004 Honda Accord."
Post Script:
As I was sitting into traffic today on i15 near the Bangerter Hwy exit, a huge jacked up F-350 Powerstroke rumbled by. If the 18" lift didn't declare "compensating" I noticed a huge red pac12 decal in his back window, Block U license plate that said "solid", and, of course, truck nutz. Didn't see the driver, but I bet he was rocking a manicured goatee, bedazzled and majorly riveted jeans, a weathered t-shirt that said "Afflicted" in tattoo script, and he was jammin out to some Heart or Nickelback.