The Obama administration is on the same page as Fannie Mae and Freddie Mac’s regulator in its desire to shift some of the mortgage credit exposure the government-sponsored enterprises hold to private investors. But exactly how to develop some sort of GSE risk-sharing program continues to bedevil policymakers, a Treasury Department official noted last week. Michael Stegman, a special advisor to Treasury Secretary Timothy Geithner, explained in a speech to real estate professionals that the Treasury is “actively engaged in helping to make this [GSE risk sharing] initiative work” but the...