If the dems decide to filibuster based on the administration's refusal to release Robert's records to them, one arguement they can make is that they don't want Roberts to turn out to be another Michael Bloom.
By that I mean, Bloomie was a nice guy who hadn't killed anybody, but who was not the right man for the job. The result was the Katrina disaster.
Roberts also appears to me a nice guy who hans't killed anybody, but we don't know enough about him to know if he is really qualified to hold the highest Judical position in the Nation. For life.
We don't want to make the same mistake with Roberts we made with Bloomie, so give us the frigging documents.
Or something to that effect.