The Obama Campaign doesn't have the need for "shenanigans", Foxie...they know only too well that the moderators in ALL these debates are already predisposed to their views. When Martha Raddatz demands "details" from Paul Ryan but doesn't ask the same of Joe Biden then it's obvious that she went into that debate with the mindset that Ryan/Romney's tax plan isn't viable because it's not set in stone how it will be finalized. Where was the demand for details about how just a tax on the wealthy will pay for all of the additional entitlements that Obama/Biden have promised? Ryan correctly pointed out that taking ALL of the earnings of the 1% would only fund government for 90 days while it would cause our economy to crater but Raddatz didn't demand details from Biden on how their plan was going to decrease the deficit.
This one was different though. You had Biden who gets it wrong as often as he gets it right, a perpetual gaffe machine who can't remember facts straight to save his life, going up against a bright, capable, very well informed, and no doubt very well prepared Ryan who WOULD remember the facts and report them competently. A sure prescription for a total train wreck in a normal debate and that the Obama campaign no doubt simply could not risk. But neither could they afford how it would look for Biden to refuse to debate Ryan.
So the solution? Just send Joe out as laughing Joe to make sure Ryan wasn't allowed to drive home a single point. And, as you pointed out, Radditz did not shy away from shutting Ryan down, cutting him off, interjecting her own follow up before he had even finished his sentence. She did not do that to Biden though she did give the appearance of enforcing time during the times he could speak--you know when he could speak unimpeded without somebody covering up his words?
Was that by design. My cynical side says probably because it was the only way they had to do damage control. Maybe not. But I'm long past believing they couldn't go that low.