I have to tell on myself. On a recent trip to Joshua Tree I was shooting mostly landscapes with my D3s when I saw a barrel cactus high up on a hillside that I wanted to get a shot of. I grabbed my 70-200 which was stowed with the tripod foot attached and my 2x tc and my D300. Without any straps on I just grabbed the rig by the tripod foot and set off across the road to get a little closer (an effective focal length of 600mm was apparently not enough for me). My hand somehow activated the release button and even though the knob was tight, the whole rig slipped out and fell about three feet to the asphalt.
It landed on the lens hood which was attached and to the flash shoe of the D300. The flash shoe was partially crushed, the onboard flash would no longer stay closed, and the camera would not shoot bursts. The camera would however still take pictures. When I later tried the 70-200 + tc on my D700 I had trouble focussing to infinity.
So I took all three items to Nikon USA here in El Segundo, CA. Will report back when they are repaired.
My conclusion is that unlike almost every other long lens, the 70-200 should not be carried by the tripod foot.