Anyone ever heard of earning points/miles while flying on a mileage ticket?

[SPGCont]

Is such a thing ever possible?

[SuperFlyer]

Normally not, sometimes yes (haven't figured whats the trigger).

When they bump you off to a next flight, you will usually earn miles, as they aren't careful to place you again on an award class.

[SuperFlyer]

Often they won't be able to place your ff# on the booking.

[yitzyul]

It usually only happens by mistake... I once was flying millage from lax-JFK with a a stopover (1 hour) in Boston (for some stupid reason they only had millage on that connection and in general allot of those tickets where cheaper). When in lax I asked a agent if there is maybe a standby open to JFK instead of Boston. ( since the final destination was the same) she then told me sure it's not a full flight and gave me different boarding pass which I got full millage for. The best part was that it was the end of the year and I was short some 2000 miles to gold and that gave me gold as well (for that year). I guess I was lucky.....

[lybbtthl]

Normally not, sometimes yes (haven't figured whats the trigger).

When they bump you off to a next flight, you will usually earn miles, as they aren't careful to place you again on an award class.

Generally, under airport control, ticket classes are irrelevant (as in when rebooking they're almost never makpid to keep you in the same class, you almost always get a higher class) unless they are doing a standard change that you would anyway be able to do by calling, but once it comes to bump/delay/cancelled etc. you will get class. Also, being that there are so many classes and only 1 (or 2) mileage classes, chances are not to end up with mileage.

Often they won't be able to place your ff# on the booking.

You should always be able to put your FF# in the booking regardless if it's a mileage ticket, there are other benefits besides mileage accrual (priority check-in, security, boarding, luggage etc.)