Let's say we assemble a package of changes to Social Security, including a diversion ("carve-out", my ass!) of funds from Social Security to private accounts that somehow manages, by the necessary combination of tax increases ("revenue enhancements," my ass!) and benefit cuts, to achieve solvency. If you put is all on a Social Security balance sheet, the diversion would have to count as an outflow...a reduction of the cash available to pay benefits.

Now. Remove that diversion from the balance sheet.

Suddenly there's a bag of money laying around. And the size of the necessary tax increase or benefit cut is reduced. Drastically.

It's that simple.