Originally Posted by
FederalFlyer
This doesn't really answer your question, but in my searches, I found that the BF fluctuates depending on the 3X. I've never seen that before. The exact same LAX-TYO-LAX flights have BFs from $68 to $523 depending on the 3X I drop in.
Yes, if you combine with DL/AF/KL/AZ/OK/AS/QX, you will get T fare (68$). If you combine with another airline, you will get L fare (523$).
So you have to find cheap DL/AF/KL/AZ/OK/AS/QX fare which is combinable with international fare.