All in all, I'm split between agreeing with Eliezer on the primacy of position, and saying 'mu'.

Probably because the original post is actually a structureless rant. The only part that makes sense is

I accept the possibility that this whole blog post is merely stupid. After all, the question of whether the position basis or the momentum basis is "more fundamental" should never make any difference as to what we anticipate. If you ever find that your anticipations come out one way in the position basis, and a different way in the momentum basis, you are surely doing something wrong.