Originally Posted by Meteorologist

I do this almost 100 percent of the time. As I see it...

Positives
1. 2000 miles from BofA for AS Visa booking
2. It is treated as two separate bookings, so if the fare on either reservation goes down, you are eligible for a voucher for a fare reduction (if within 90 days of purchase). If you bought a round trip, the fare of the entire ticket would had to have gone down. (I've actually argued this on the phone with AS to no avail when booking a RT reservation, so I will no longer do that.) Example: SEA-GEG on your outbound was $59 and reduces to $49. GEG-SEA on your inbound was $59 and increased to $69. If the RT was one ticket, you'd be entitled to no fare reduction voucher because your net fare change would be $0. If they are booked separately, you'd get $25 (I believe this is the smallest increment they will issue) off a future flight because of that first leg going down $10.

Negatives
1. Quick turnarounds. If you are flying a route like SEA-GEG and GEG-SEA in the same day, there may be benefits to having it on one reservation in the event of IRROPS.
2. The MVPG desk gets annoyed when you call and they have to access to separate PNRs every time you reference a trip you're taking
3. Increased change fees by paying per PNR if a non-MVPG

Also, if you need to change a ticket online, and the fare is even $1 higher, you will get another 1000 mile booking bonus from BofA. Just a little hint there