It is in our ops manual as a requirement to use D2 in the climb phase. If a constraint cannot be made on the SID then other than going to selected speed the derate can be used to D1 or taken out totally. Question I am interested in is how does your company require you to take out the derate. I personally clear it on the MCDU but some guys I fly with move the thrust levers from climb to MCT and back again.
The Cav