I think flyby was referring to the dreaded hourly rate, which BASSA has poisoned crews mind against. It evens out the amount you earn by locking in a higher basic (I guess by the equivalent of MTP), and means all destinations are equal so you can bid for what you want, not what pays most.
I have never met a crew member who understood the hourly rate, they always say "it would mean £2.70 an hour and I can't live on that".
Another example of dreadful reps. this could be a real advantage to crew and BA but no crew/rep will even examine it as an option.