Excuse me if I'm speaking nonsense, but I think I remember Rockwell's writting about cameras don't matter and, if my memory doesn't fail, it was about film cameras. That doesn't eliminate the discussion at all, but it does make some important difference: the huge differences of sensors and pixels don't count there, since the film you're using is the same in both cameras. So that would be like having the D700's sensor on a disposable P&S!
Then the "only" difference that remains is that which has to do with controlling the camera vs letting the camera decide everything, maybe ramdomly. And -again, trusting my memory- in this regard Rockwell minimized that difference by referring to shoots in which one can somehow "control" a P&S camera: well lit situations, without a particular need for a controlled DOF, without action, etc
So the point could look somehow tricky but there was a serious point, seems to me: as some have written above, stop worrying about the gear and start shooting. Nice pictures will come out of a lot of a nice subject, a beatiful light... and a lot practising, not out of upgrading equipment.
And finally, as for the irony in that coming from a fetish camera gear man, it does contain a lot of irony, but on the other hand it can also be viewed as a way to balance the fetishism. And I am NOT trying to speak in favour of Rockwell in any way. As a matter of fact, I am not particularly fond of the guy... to express it nicely