But even though immunized, Ari may be fibbing.  His vanity may have motivated him from day one to deny any awareness of classification of the status of Wilson's wife and therefore explain why he talked about it at all.  He had two choices -- admit he knew she was classified and blabbed about her anyway, or admit he knew nothing of her status and blabbed freely.  His ego may have caused him to commit to a story early in which he blabbed more freely because he allegedly did not know of covert status.  Why fib if immunized -- because he still does not want to look like a dick.  Plus you have to realize how people reconstruct memory of things (I am a trial lawyer) -- they want to remember in a way that denies that they were stupid louts who did not care about proper security.

I also recall that part of the story was that a briefing book (for Powell?) was on Air Force One that had the info about Plame and clearly showed it as classified (this was not brought out in Ari's testimony).  Allegedly, this info was viewed by many during the flight.  This suggests to me that Ari may have actually known of the classified nature of it, and yet participated in the whispering campaign to use the nepotism claim to smear Wilson.

Also, according to Ari's story, he was told by Libby that it was "hush, hush and on the QT" and then he turns around and blabs it to Dickerson, et al.  I don't know which is more ridiculous -- that Libby actually said this or that Ari claims it.  Maybe Libby did more than this and actually indicated to Ari that she was classified, but that they nonetheless talked about how to get the dirt out?  In any event, what made Ari think he could be so free about it later with Dickerson even if only "QT protected"?

Even though immunized, Ari still has the motivation to tell the story in a way most flattering to him.  In fact, people have a weird way of remembering bullshit because they want to remember it that way, and they are not necessarily "lying" in the deliberately false sort of way -- more like creatively re-remembering it.