To expand, for the Regs Wizards out there, my understanding is that a circling maneuver is a portion of an instrument approach, therefore the protected area applies. I'm pretty sure that the protected area would allow one to fly MUCH further out from the field than NY Approach wants you to go (for the aforementioned conflicts with traffic to other airports), so when you say "circle to 1", you're not really flying a circling maneuver on a charted instrument approach, you're flying a visual approach to a different runway. Which is fine, as long as we are all clear on what's going on. I'm not sure we all are. It being TEB, there's an enormous amount of pressure to move metal, and a few steps may be getting skipped. It will be interesting to see what the NTSB (and subsequently the FAA) wind up saying about this sad event. I would give dollars to donuts that there will be some sharpening up on what various terms mean and what a pilot's (and controller's) responsibilities are in various categories of approach. Always has to be written in blood, doesn't it?