McMohan - 8:34 am on Oct 24, 2012 (gmt 0)
Disclaimer: This school of thought might already have been proposed in some threads, if so please remove my post.
Assumption: My shot at Penguin recovery is based on the premise that Google can't penalize your site based on inbound links, unless there is concrete evidence that you own those sites that are linking.
If the above premise is true(which I personally believe is to be true), then what good is going to come from removing links to your that were not the cause of a "Penalty"?
Penguin mainly affected sites that relied heavily on keyword anchor text backlinks, from sites where links can be obtained without breaking a sweat (read bookmarking, forums signatures, blog comments so on). In all likelyhood, Google merely discounted those links, as if they didn't exist. Google has in fact done the "link removal" for you. Since the sites relied heavily on such links enjoying the ranks they did, when those links were discounted in a bunch, the fall was obvious. Penalty is not the word.
Now, if those links didn't exist and so do the ranks, what is to be done? Get new links, that are Penguin-proof. From sites where anyone and everyone can't get links, relevant and natural anchor text. It is the addition of such links that matter (IMO) not the deletion of crap links.
None of the sites I deal with have been affected by Penguin (touch wood) and I do not have the first hand experience of pulling through any site from Penguin, but I have studied a good deal of Penguin affected sites.