Jez123 - 3:56 pm on Oct 19, 2012 (gmt 0)
Keep in mind that Matt Cutts said that links should only be disavowed if you received an unnatural links notice.
He didn't just say that. He mentioned Penguin as well. Not all Penguin affected sites got a notice. Also, google said don't bother to submit a reconsideration if your site is hit with Penguin as it is not a manual action.
As usual it's confusing at best. I have submitted anyway even though I have no manual penalty or spam links notice. Nothing to lose.