The second reason I've given is that it would set up a Rock v Ryback match at the 2013 Royal Rumble, or necessitate having the title back on Punk by January. A clash between 'back and 'The Great One' doesn't seem like a match WWE are interested in, and taking the belt off of Punk just to put it back on him within three months seems short-sighted.
But what if I'm wrong? It's not as though promoting Ryback to the top of the card is without merit.
As I've noted before Ryback would be a welcome addition to a barren main event scene. A victory over Punk would undoubtedly be the best way of establishing him as a headliner. Plenty of fresh bouts would be created by the move. Alberto Del Rio, a heel Randy Orton, Big Show, and Dolph Ziggler could all solidify Ryback's standing as the new top man. A face versus face encounter with Sheamus could be interesting, and rematches with Punk would help too.
Look how excitable Ryback is. Imagine if he became champ!
A promotion of Ryback would really pay off come WrestleMania season. All of the big players whose 'Mania outings are currently being discussed would be fresh opponents for Ryback. If 'The Human Wrecking Ball' were still undefeated, and champion to boot, then he could realistically be paired up with any of them for a money-drawing first time encounter.
The Rock, Undertaker, Triple H, Brock Lesnar and John Cena are the men in question. They, along with CM Punk, are expected to form the basis of WrestleMania XXIX's top matches. While the exact matches haven't been revealed knowing the men who will be in them makes the event a little predictable. Adding Ryback's name to the list would create some uncertainty along with some buzz for the new boy.
If 'The Human Wrecking Ball' were to head into the Rumble as champion he would be facing The Rock. Having him beat 'The Brahma Bull' would further enhance his standing and be an unexpected result, because most people are expecting Rock v Cena II for the championship at WrestleMania.
An argument against that happening is that a match between current champion CM Punk and The Rock has already been hinted at. Said hints cannot be taken back but that's not a bad thing. It would just make a Ryback v Rock match that more surprising when announced.
Were 'Big Hungry' to beat Hollywood's finest at the Rumble it would open up plenty of options for WrestleMania. He could take on the boss and be written into a feud with (a heel) Triple H. He could give 'The Great One' a rematch. He could battle with a Rumble-winning CM Punk. He could face WWE's prize box office acquisition Brock Lesnar. He could challenge the Undertaker's Streak, allowing for marketing to focus on an "undefeated" star challenging 'The Dead Man'.
Ryback could even be booked against the company's current top guy, John Cena. A face versus face clash between the two wouldn't be pretty and would see 'The CeNation Leader' get heavily booed (which will happen no matter who he faces on the snow) but it would also present Ryback as heir apparent to the top babyface spot.
Do I think any of the above will happen? No. I'm sticking to my prediction that Punk will leave HIAC still WWE champion and be the man to lose the title to The Rock at Royal Rumble. There are ways of protecting Ryback without putting the belt on him. Matches between The Rock and both CM Punk and John Cena have already been hinted at. I don't think WWE is going to change course now.