Should I be concerned about IB? I'm doing 3 sectors domestically with them next week. BCN-MAD, MAD-VLC, and VLC-BCN. Booked through 3 seperate reservations with 3 different FF's. This is the only way it will work.

I did SYD-x/CBR-MEL-x/CBR-SYD on a full fare Sydney-Melbourne-Sydney ticket but called Qantas up 4 times to book each sector seperately. When check in printed my boarding passes, all the flights (SYD-CBR, and CBR-MEL) reflected the different FF numbers. Check in staff do not ask questions. As long as they see your name on the computer for the flight booked, that's all they are concerned about. In fact, most of them do not know actual ticketing rules!