My only comment is that NW International FAs tend to be particularly nasty in determining what one can and cannot carry on board. Elite status, first to board, etc appears to have no bearing. The individual standing at the door tends to force one to check carry on baggage that is within their own standards with no discernable reason, simply because they want to. It is wise to go with the expectation that you will be forced to check a carry-on at the door.
This policy is one reason why I avoid NW whenever possible.