I still don't think anybody has a fucking clue about what an actual Penguin penalty entails or how long it lasts. The most common accepted definition I could find was a keyword specific (ie, not sitewide) penalty, generally brought on by over optimizing your backlink anchors for that specific keyword(s) you're penalized for.
If the above generally accepted conclusion (groupthink, ain't it grand?) is correct, than penguin has nothing to do with time or data refreshes. If your backlink profile is still fucked up when penguin refreshes after a year (if it does), you're still penalized. If you can fix it sooner (say, six weeks allegedly), penalty goes bye bye.
tl;dr: SEO(s) is(are) stupid.