You can't do that. The gate agents are instructed to assign a seat in the cabin if one is available. Requesting the 1W can get your travel benefits revoked if you anger the wrong gate agent. We apparently don't have a right to the jumpseat when seats are open. Please don't ask me how I found this out or why I needed a union rep to go and talk to my chief pilot about this travel policy - just believe me and it should be in the travel book.