Because the Dems overstepped with Bork and Bush wasn't a lame duck like Reagan was with Bork.
They overstepped with Bork, so to show their political savvy they crucified Thomas?
The point is, forget about how tough the confirmation is. When it gets down to it, the congress is still majority Republican whereas the Democrats controlled in Thomas' case. Delivering the questionable votes that you point out doesn't take into account the fact that the President still wields power over GOP congressmen, ESPECIALLY with a mid-term election on the way. They might add some drama to the proceedings, but in the end, they would vote party-line on Jones, Luttig, whoever. We can't compromise because we're afraid someone MIGHT not get confirmed. That's defeatism at its worst because it bastardizes what we stand for.