brakes fan misuse
As far as i know the brake fans are on optionnal eqpt according to he type of operations(ambiant temperatures, rwy length, ldg weight).
This equipment is very useful during short turnaround (no suffuciant cooling time).
As said in many posts, brakes wear and temperature will depend on many factors ( number of applications, ldg weight, Vapp etc)
So in my opinion, I recommend not to use the brakes fans after lading ( even after the 5 min ), except if the brakes temperature tends to exceed 500°C,let the brakes cool ''naturally'' at the gate during turnaround.
After doors closure and just prior to pushback or taxi out, running the fans would be sufficient to reach the rwy with an reasonnable brakes temp (less than 150 ° fans on)
Totally agree with bolty (post 9), cos running the fans when reaching the gate seems no sens, just imagine the symphony played by many busses parked in the same area,and the carbon dust sprayed into the noses of gnd personnel.
cheers