We got lucky with Rehnquist. Sometimes people win the lottery - it doesn't mean that investing in lottery tickets is a sound practice.
Why not nominate a known quantity for such an important position?
I wonder if those who supported and respected William Rehnquist when he was nominated and years later looked at it as "luck"....as you apparently do. It couldn't possibly be that someone knew more about him when he was nominated than the political couch potato.