I dunno seamole. It looks like a slam dunk the way it is presented.
He tells the GJ that Russert asked Libby if Libby knew about Plame.
But Russert says he did not ask. (he said, she said)
He tells the GJ that he (Libby) was surprised by the fact (learned from Russert) that Plame worked for the CIA.
But Libby knew Plame worked for the CIA based on Libby's independent research, only a few weeks old (no he said, she said in that lie - it is self contained as to Libby's personal state of mind)