The day that Romney finally relented and released the two years of returns, Stephen Colbert said something on his show that I think was right on the money, but for some reason it hasn't been picked up or talked up anywhere. It's probably better to save as ammo for the campaign during the general election, but I wanted to make note of it so that we don't forget when it comes time.
On Romney's 2010 return Colbert noted that he had carry over 'losses', and posited that it probably meant that Romney hadn't paid any taxes at all in 2008 and 2009. I agree with his assessment, the meltdown was 2008 with the economy in freefall for the back half of that year and well into the next, and since so many people took major hits that it wouldn't be surprising that someone whose only income was off 'previous investments' wouldn't have nearly as much coming in. We can safely assume that he's got very expensive and creative tax people who do nothing but look for ways to get him out of paying 'one dollar more' than he has to. Plus we know that he sent how many years' worth of returns to McCain for vetting? So there's unlikely to be anything earth shatteringly embarrassing in those old ones, but if he released the old ones and only skipped 2008 & '09 it would paint a big glaring spotlight right dead on where he was not wanting anyone to look.
How would it play given OWS and all the attention on his clueless rich boy issues if the guy who made more in a day than the median American makes in a year, the guy who's worth how many hundred of millions?, if to add insult to injury he paid no taxes at all for two years where everyone else was struggling and so many were losing jobs and homes and needing food stamps?
I really think that this is what he's trying to hide with his short nod towards disclosure.
Sorry this is going to be a drive by, no internet access at home right now, but I haven't seen this addressed anywhere and the places I put it in comments were so late they didn't get noticed.