I just thought I would share a little info that I found recently in the newest 5-series Bentley Manual (E60). In the Transfer Case section, under clutch actuator (VTG) motor, it states:

“Because of mechanical tolerances in production, the characteristic curve of the multi-disc clutch locking torque varies slightly. At the factory, once the actual locking torque is measured on the clutch test bench, a resistor is attached to the clutch actuator. The resistor value (Classification) determines clutch locking torque characteristics.
1. Clutch actuator drive gear
2. Clutch actuator (servo motor)
3. Classification resistor
Each time the engine is started, the transfer case module measures the resistor value once and selects the optimum program map for transfer case engagement.”

Also, in the Transfer Case Fluid service section, the only mention of electronics is that the transfer case control module monitors oil life to determine when the oil is to be changed. There are no other caveats other than to use the correct BMW oil, filling to the bottom of the fill hole and torque the drain plug to spec. Although this TC is the ATC 300 rather than the 700 (X5), the procedure is consistent with my version of the TIS for the ATC 700.

So it seems there must have been a change in the software that required previous versions to have it reset with the dealer computer whereas now (>2009) it appears to reset itself upon startup.