Per OP's 2nd link "SECURE FLIGHT FINAL PHASE," dated Oct 20, 2010:


"As a rule of thumb, it is best to enter into the name field of the PNR the passenger’s name as it appears on the valid government-issued photo identification used to provide Secure Flight Passenger Data, matching whatever type (passport, drivers license, etc) of valid government-issued photo identification is presented.

International Travel
• Name on Passport: Thurston Backus Howell III
• Name Field in Reservation: Howell III/Thurston (NOTE: the middle name is NOT required in the Name Field, but the suffix IS required in the Name Field when using a passport for DOCS/P SSR; it must be an exact match to the passport)
• APIS: 4DOCS/P/US/1234567/US/01JAN35/M/01MAR17/HOWELL III/THURSTON/BACKUS-1.1
• Secure Flight Passenger Data: 4DOCS/DB/01JAN35/M/HOWELL III/THURSTON/BACKUS

Domestic Travel
• Name on Drivers License: Thurston Backus Howell III
• Name Field in Reservation: Howell/Thurston [(NOTE: the suffix “III” nor the middle name is required in the Name Field; the suffix is not required when using government-issued ID such as a drivers license)
• Secure Flight Passenger Data: 4DOCS/DB/01JAN35/M/HOWELL/THURSTON/BACKUS

We also suggest that passengers use the same valid government-issued photo identification. A passport, for example can be used for both domestic and international travel, whereas a drivers license can be used only for domestic travel."

This appears to have caught AA.com by surprise, as the section under "Secure Flight Information" shows the "Last Name" field followed by a "(no suffix)."