Janspeed,
Good to get some empirical evidence. If it feels like "you have hit something" at 72 knots then it is deffo more aggressive than Mr. B's max braking equivalent.
Al the dinosaur said the Airbus view is max auto brake SHOULD not be used for landing (as opposed to MUST not). This gives the crew discretion to use max auto brake in the emergency unfactored performance landing on a short runway.
Both your posts point to an abort at Max TOW (however much heavier that is than max landing weight) at V1 resulting in tyres exceeding fuse temperatures. The higher speed and higher weight do not have a linear relationship and I would be surprised if the energy dissapated by brakes in the MTOW V1 case is not twice that of a relatively slow speed max landing weight. Not Airbus qualified so some numbers would help from those that are.