I listened carefully as Jeff Bewkes and Randall Stephenson made the TV rounds yesterday, explaining why they thought their planned merger of Time Warner and AT&T was a winning idea.

It has nothing to do with giving AT&T customers preferential access to Time Warner content, Stephenson told CNBC. “That’s nonsensical. We’re buying Time Warner for $100 billion, including debt, and they have built this amazing franchise, distributing their content broadly and deeply all over the world. The idea that we’re going to come along and start to constrict the distribution of this content makes no economic sense. That would be a crazy idea.”

Stephenson didn’t directly address the notion that AT&T might “zero-rate” Time Warner content – meaning let its users watch without counting against their data packages. The company has already said it plans to “zero-rate” Direct TV. It’s that kind of uneven treatment that will put the “net neutrality” advocates on the warpath.

Let’s assume Stephenson has no intention of favoring Time Warner content, even with zero rating. Then what’s the benefit of the deal? Bewkes claims the two companies can innovate together better than they can alone. “We realized that if we had ourselves together that we could create more innovations for consumers so they can have more choices of packages. They are going to end up with more competition therefore lower prices.” (Not clear why this sort of innovation wasn’t possible with Time Warner Cable, which Time Warner spun off five years ago.)

Can a giant combo-company really win the innovation race better than, say, two smaller, more focused ones? Just the process of integration will consume both behemoths for months. And my experience in the media world leaves me convinced that deals between divisions of the same company can be every bit as difficult, if not more so, than deals between separate companies – especially when they disrupt existing revenue streams. (The disastrous AOL-Time Warner merger was a case in point.)

So count me skeptical. And count the markets skeptical, too. Yesterday, Time Warner stock was trading at around $87, well below the $107.50 offer price.

Incidentally, if the deal does go through, Jeff Bewkes should be celebrated by his shareholders as one of the great media titans of our times. Fortune’s number crunching shows that at the deal price, he will have delivered shareholders an annualized return of 17% since becoming CEO in January of 2008. That would top Disney CEO Bob Iger’s return to shareholders over the same period, and roughly match Comcast CEO Brian Roberts’.