One very obvious reason why CIPA and Nikon's test numbers vary so widely for the D700 as compared to the D3 is because the D700 has an on-camera flash. CIPA require a full illumination flash exposure every second frame. That causes a lot of draw on the D700. The D3 hasn't got an on-camera flash so it's battery last twice as long. So the D3 numbers probably more closely reflect what you'd see from a D700 using the MB-D10 and EN-EL4a with an SB800 fitted instead of the on-camera flash.