"On the 320 'minimum runway' occupancy meant MED autobrake and FULL reverse..."
Max reverse or idle reverse... Autobrake provides a decelleration RATE. If you use idle rev it will brake accordingly to achieve a rate and max reverse same.. Brakes will vary accordingly to achieve a decel rate...
Min runway occupancy is med autobrake.. Idle or max rev
You'll still pull up at the same decel rate...
The only think affected is brake temperature.