Let's pretend, for a second that all the other reasons why the cries of "runaway prosecutor" from the Libby Lobby don't exist. Set aside the fact that the FBI and then Fitzgerald were investigating all leaks of Valerie Wilson's identity, not just those to Robert Novak. Set aside the fact that the 1X2X6 story (as well as the clear evidence of at least three leaks by October 12, 2003) didn't have the FBI looking for more than one leaker.
The claim that Fitzgerald should not have investigated beyond the the day when, on October 1, 2003, Armitage identified himself as the first source to Novak would still be wrong.
That's because there were clear discrepancies between Armitage's and Novak's stories. And Fitzgerald was actively investigating Armitage and Novak at least until September of 2004. The FBI couldn't close up shop on October 1, 2003, and Fitzgerald didn't close up shop on December 30, 2003, because it was still trying to determine whether Armitage had leaked Valerie Wilson's identity to Novak intentionally for at least nine more months.
The newly unsealed portions of the affidavits Fitzgerald wrote in pursuit of Judy Miller's and Matt Cooper's testimony make this clear (I'm getting these scanned--I should have links to them in the next day or so). In the Miller affidavit, Fitzgerald lays out some of the discrepancies:
Novak and Armitage agree on several important facts, such as the time, date and place of the meeting during which the conversation took place, and the fact that Wilson’s wife and employment by the CIA was disclosed to Novak by Armitage in response to a question by novak as to why the CIA had sent Wilson on the trip. Their testimony diverges as to whether Armitage provided the first name of Ms. Plame, though both agree the last name, “Plame” was not provided. Novak recalls being told by Armitage that Wilson’s wife worked in the area of weapons of mass destruction --[redacted] Armitage does not recall discussing the area in which Wilson’s wife worked. Novak and Armitage give differing accounts of other materials not germane to the instant motion. The investigation of Armitage’s conduct is ongoing. [my emphasis]
And the affidavit on Cooper reveals that Fitzgerald was actively
interviewing both Armitage and Novak in fall 2004. Novak gave a
follow-up deposition on September 13, 2004 [though there's an error in
the affidavit, I think]. And Armitage testified to the grand jury a
second time on September 22, 2004. (And, as a reminder, Rove testified
for the third time in October 2004, so he was likely asked about
several of these discrepancies.) And, by this point, Fitzgerald knew that Libby had met with Novak on July 9, but had lied about doing so on multiple occasions.
The Libby Lobby complains that Fitzgerald should have stopped investigating when he stopped investigating Armitage. They complain that Fitzgerald didn't scrutinize Armitage's actions as closely as he did Libby's.
Any bets on whether we'll stop hearing this refrain now that it has been proven false?