No SCOTUS decision has the power to automatically "off" itself after 25 years. O'Connor was expressing a breezy personal opinion and desire--not invoking a sunset provision.
Yet Congressman Billybob's analysis makes it sound as if the "25-year and out" thing is a done-deal. He knows better. I suspect it was just sloppy writing on his part.
All the undergraduate decision did was force admissions committees to be more subtle in carrying out their racist policies in the future. Hard quotas and race-based points are out. Now they will simply reach the same result through a process of zen-like touchy-feely subjective analysis in which certain racial characterisitics will override objective factors.
Why will they do this? Becuase admissions committees are unabashedly liberal and believe fully in affirmative action. They will warp and twist the decision to keep affirmative action the focus of how they do their work.