Adam Clymer encourages Romney to release his returns already:
The subject may come and go in the summer, but it won’t go away. Someday, in the debates with Obama if not before, Romney is going to be questioned more intensely than he has been so far, and what will he say when asked, “Have you ever paid federal income taxes as low as 1 percent of your income? Five percent? What’s the lowest you ever paid?”
He'll say it's none of our business. Which makes his candidacy an almost defiant defense of the privilege of the super-wealthy. The 0.01 percent don't have to abide by the same rules as everyone else. Romney has lived his life by that maxim. It's internalized. One question in this election is whether Americans really want that social and economic inequality to be put on steroids or whether they want to see it mitigated a touch.