Sure, I understand that and certainly it would seem that the FPP scale is indeed engineered in a way that BA effectively get the money back off you that they invested in your TR. I wonder if this scale will be altered as a result of the 34PP scenario which seems inevitable.
It seems as though the FlyBe cadet schemes are unique in that they do not 'cost' the cadet anything for the TR. This is paid for you and you go in on the same scale/salary as anybody else would.