If you want to now jump to the 'everybody forgot things' saw, then we may as well take perjury off the books because there will never be a trial with witnesses who haven't forgotten things.
NINE people had conversations with Libby. We know he knew about Plame. If he had done what Rove did, and corrected his story before the GJ, he never would've been prosecuted. He played with fire instead.
If you examine their testimony carefully--most of their memories improved with time like vintage wine--and at most the conversations were about 30 seconds long at a time when (pre Corn's Emma Peel story) the information wasn't memorable and there was no evidence Libby heard whatever they said.
What did the nine people testify?
I know what Ari said, and I know what the other eight said.
Please tell me how (with the evidence and testimony), they found him guilty on four counts.