If (please note the use of this word) Libby lied under oath, he should be charged with perjury. If Libby did not lie under oath, he should be exonerated.
I don't care if there was or was not a crime to lie about, the lie itself is an undermining of the judicial system.
This is why Clinton was impeached and why he should have been removed from office. I didn't care that he was having an affair. I didn't care that he was involved with a woman his daughter's age. I didn't care that he didn't even have enough sense to be discreet. I did care, very much, that he lied under oath. Perjury, even about a non-crime, is a form of eroding the system of justice that is the foundation of our Republic. It is a high crime. It is a felony.
So, if Woodward's testimony shows that Libby was not lying, this is important for Libby. If this just shows, again, how this was a political witchhunt, then Libby still needs to have the allegation of perjury examined.
That's too black and white. You leave no room for the fact that his memory might be at fault -- it has been 2 years, you know.
Perjury is a separate issue and charge, which Libby has to answer for.
However...Customary practice and DOJ guidelines state that before the investigatory nachinery of the government is brought to bear, there should be some case that a law has been broken. diGenova and Toensing have been saying from day 1 that there was no crime. There's at least a hint of prosecutorial misconduct, which Fitzgerald would have to answer for. Any competent defense attorney would seek to have the case thrown out on those grounds.