Thank you Rocky. Eyeballing that, even on my iPhone the difference is clear. Good to know when thinking about ones AF shooting style. It motivates me to go back and do this for D300 and D7000. Prompting much thought... anyhow I love the D7000 form factor and U1/U2 so I think the D600 will be a great camera to shoot although I'd have to modify my AF habits.
But you just gave me additional motivation for my D400