In general I agree with you, but my point was they are published as legal. Rostering into discretion is something I have never seen nor been made aware of by any Balpa member.
Discretion has always been the Captain's decision.
The fatigue-making rostering is a major problem but the issue remains the dreaded burden of proof. The CAA have never set the criteria for a definition of fatigue.
From the Balpa side we are moving towards an improvement - hopefully very soon ( God I hope so!), but like all things, some will be happy..........some never will!