You also have to factor in earn/burn. How fast are you spending a frequent-flier mile after you earn it?

For example, if I hold the AA Citibank Card, I'm paying roughly 1.5 cents for every mile I buy from Citibank. I say 1.5 cents because that is the current best no-bull cash-rebate credit card (offering by Fidelity, I believe). I'm trading that 1.5 cents for 1 AA mile.

So...if I am earning those AA miles and turning them into award flights that I would have otherwise bought with cash, it's pretty easy to value the miles. If I'm the kinda guy that usually buys discount-Y out of my own pocket, I might get 1.5 or 2 cents - we all know roughly how that works. If I'm a high-roller and I ordinarily buy walk-up F tickets for vacations, then I can justifiably say I'm getting 8 cents or whatever.

But...here's the problem I have run into in the past...I have too many FF miles! The oldest AA mile in my account right now was probably earned in 2000 or so, using FIFO. That means...if I used the AA Citicard to "buy" that mile, I got hosed royally. Unless I'm that walk-up F traveler.

So...what does this mean? We are all forced to "buy" miles when we fly. That is, if I buy an AA ticket, I'm paying for the miles associated with that whether I want 'em or not. But...I have since learned to never buy a discretionary FF mile unless I think I am really going to use it. I'm not going to buy a $60 product bundle of flowers and frequent flier miles when all I really wanted was the flowers that cost $20 on the street - without miles. I'm not going to buy AA miles every time I pull out a credit card - I'll instead buy something else, such as the rebate or a hotel point that I know I can use quickly.