And while the wisdom of this edict is open to debate, CNN's biggest problem isn't the talk-radio personalities who appear as guests, it's a talk-radio personality who appears as a host.
Lou Dobbs, for example, has been getting increasingly nutty as the year progresses, and this week he lashed out at Howard Dean. "I thought we had gotten rid of this left-wing pest for a while," Dobbs said of the former Vermont governor. "But I guess he is just resurgent.... He's a bloodsucking leftist. I mean, you gotta put a stake through his heart to stop this guy."
When some suggested such over-the-top rhetoric might be inappropriate, Dobbs backpedaled ... a little.
In a statement to the Huffington Post on Tuesday, Dobbs made a quasi-apology, wrapped in a dig at his critics.
"I'm sorry if a Bram Stoker allusion is too literary for some, and for those who could not make what was seemingly an obvious connection, my deepest apologies and I'll gladly withdraw the latter part of my remark," Dobbs said.
To clarify, Dobbs went after Dean on his syndicated far-right radio show, not to be confused with his CNN program. Indeed, CNN execs routinely emphasize the distinction -- what Dobbs says on the radio is of little interest, they say, because their interest is what he says on CNN.
But these efforts to split Lou Dobbs in two -- as if the CNN Dobbs and the radio Dobbs were somehow different people -- is unpersuasive. Like it or not, CNN, which aims to be "the most trusted name in news," pays a rather nutty demagogue quite a bit of money to host a daily news program, which has routinely focused on bizarre far-right conspiracy theories.
CNN's Klein told producers, "Complex issues require world class reporting." I couldn't agree more. But with this in mind, what's the defense for keeping Dobbs on the air?