I fly big, tall airplanes, and still get clearance from the mech on the headset before pressurizing hydraulics!
For those who don't know airplane sstems, electric hydraulic pumps are not activated every time electrical power is on the airplane. There are separate switches for each pump, and they are turned off immediately after engine shutdown. They are not turned on until said clearance is received in the midst of the Pushback/Engine Start checklist.