B737NG FMS - Cruise Wind entry?

[ATRflyer]

Hi all,

Just have a few questions about the cruise wind entry in the Performance Initialization page of the 737NG FMS.

If you put the forecast wind for your cruising level in the CRZ WIND line, would I be right in saying that the FMS will use the actual wind sensed by the ADIRS for calculating the ETA for the active waypoint; and all ETAs for waypoints along the other legs of the route will be calculated using this entered wind data?

The boeing manual says that if no entry is made, the FMC assumes zero wind for preflight predictions. This sounds very straight forward but what happens once your in flight? Would it use current wind for the active waypoint and zero wind for all other waypoints along the route?

Thanks in advance,

Regards,
Atrflyer