Originally Posted by
LondonElite
You can easily have two seats on the same flight. People transporting a double bass do it all the time.
... Your chances are probably improved if you didn't include your FF number on one of the bookings. ...
It has been reliably reported in several places, including quite a few FT threads, that some cellos have their own FF numbers. (A double bass in a case would be a tight squeeze in a domestic F seat, I should think - to say nothing of getting it there through the door and down the aisle.)