Thank you for contacting nwa.com Online Support.
Following is the transcript of our conversation.
_____________

Q: From: Old Gold
nwa.com Reservations

In the past I've been able to purchase NW tickets without a WorldPerks number, I'm a OnePass Platinum Elite, what's the problem now?

A: Hello, you have reached AJ with nwa.com Customer Service.
We now require that customers have a WorldPerks number and PIN to book on nwa.com. Customer feedback indicated that maintaining separate membership numbers and PIN/passwords for WorldPerks and nwa.com Reservations caused confusion. In response to this feedback, a WorldPerks number is now the only number needed to use nwa.com Reservations and other nwa.com services. I apologize for the inconvenience this change may cause you. While you are unable to register for nwa.com Reservations with a Continental frequent flyer number, you are able to select the frequent flyer program of your choice during the booking process. This will ensure that you continue to earn flight miles for your One Pass account. If you don't have a WorldPerks number and PIN at this time, please enroll by visiting our website at
http://www.nwa.com/freqfly/direct/enrol/
Thank you for using Internet Support. Should you need additional assistance, please click on "Ask Another Question."

Q: Why should I have to sign up for a frequent flyer program that I don't intend to use in order to buy tickets for your airline?

A: Hello,
Using your WorldPerks number and PIN for all nwa.com services is designed to simplify your access and will permit us to better serve you. Customer feedback indicated that maintaining separate membership numbers and PIN/passwords for WorldPerks and nwa.com Reservations caused confusion.
Thank you for using Internet Support. Should you need additional assistance, please click on "Ask Another Question."

Q: Having to get another FF account # and PIN doesn't simplify the process for me, when did this stupid policy begin?

A: We changed our reservations website on September 6, 2002. Thank you for using Internet Support. Should you need additional assistance, please click on "Ask Another Question."

Q: OK, I guess I'll have to use another booking engine IF I decide to buy a NW ticket.

Hello
We will be sure to pass on your comments. I apologize for any inconvenience that this has caused you.
Thank you for using Internet Support. Should you need additional assistance, please click on "Ask Another Question."