When I worked in reservations in the mid 1990s, the Flying Colonel was explained to us during training that it was some sort of recognition given out by the marketing department. But we didn't do anything special for them, like during IRROPS, like we did for SM/GM/PM. The pax's Medallion status determined the extent to which assistance was offered. Yes, "FC" showed up on the PNR next to the pax's name, along with their Medallion status if they had one.