Hey, all:

The cool thing about this board is that people listen and explain it in the way that I can comprehend. I wish the NWA agent had done it like you three had outlined so simply and yet so clearly -- perhaps then I wouldn't have gotten so defensive and frustrated.

I suppose the way I was viewing the "ownership" of PD certificate is not what it actually is. PD is indeed a discount coupon that NW provided for me to lower the base fare, and once used it is gone and NOT recoverable. The latter part is frustrating, but now I that I liken PD to a store coupon, I see my assertion is not so reasonable.

Thanks all for helping me learn this.