How we cite our quotes: (Section.Subsection.Paragraph) or (Section.Paragraph)
Quote #4
The burden applies with even greater force to excised material; once the decision is made to excise, the material is restored to its privileged status and should be returned under seal to its lawful custodian. (IV.E.3).
The Court's saying that the district court has no right to keep subpoenaed material that's irrelevant to the case. It's once again considered privileged and it's the responsibility of the court to return it to the legal owner. They're trying to be very fair about this even while requiring the release of information that is relevant.
Quote #5
We conclude that when the ground for asserting privilege as to subpoenaed materials sought for use in a criminal trial is based only on the generalized interest in confidentiality, it cannot prevail over the fundamental demands of due process of law in the fair administration of criminal justice. The generalized assertion of privilege must yield to the demonstrated, specific need for evidence in a pending criminal trial. (Syllabus.5)
This is the Court's final decision that the use of executive privilege can't get in the way of the investigation of a criminal trial. This is probably what Nixon was afraid of: that the Supreme Court, being a judicial body, would think that the administration of justice was the most important thing. Imagine.