Hit By Manual Action? Donít Mess Around: Both Remove & Disavow
I think the reality is two-fold, however. First, many of the sites impacted by things like the Penguin Update and seeking to remove bad links may have many of them, so that by removing a few, the link disavow tool can help as part of an overall clean-up effort
Second, I actually think the link disavow tool isnít trying to do some type of cross-checking. If you were hit by an automated action like Penguin based on your backlinks, rather than a manual action, I suspect that just disavowing those bad links (if you can tell what they are) will be sufficient. If you read the comments from Cutts closely, his statement is more about what Google could do, not what it necessarily does.
But having said that, his is the official advice, and so if you think you were hit by a penalty, Iíd follow it fully. Try to remove some of those links manually.
Moreover, if you were hit by a manual action, where you know some human at Google has penalized yourself, youíre going to be under even more scrutiny when filing a reinclusion request. That means youíll want to know that if a Google web spam team member checks on their site, theyíll see youíve done more than just disavow links.