Fein on Forcing Oversight on the Unitary Executive

Via FireDogLake, we have a Bruce Fein editorial on a method for forcing the notoriously tight White House to give up some information to Congressional oversight. He proposes:

A Democrat-controlled 110th Congress must enact new legislation to challenge executive privilege if it hopes to exercise meaningful oversight of the White House. The legislation should establish House and Senate legislative-executive committees featuring legislative majorities to arbitrate disputes over congressional access to national security information.

Ummmm, Bruce? I love you, man, but how is that going to work? Perhaps I'm ignorant of some ability of the Congress to enact this type of legislation without the signature of the President. Barring that, though, the idea of Bush signing a law designed to allow the Congress to investigate him is what some might call naive. It should go without saying that we wouldn't have the votes to override. So what's the esteemed Deputy AG talking about?