SSD
I agree with what you are saying it is a bad piece of planning and why would you want 40 degrees unless landing on the shortest runway with a steep descent?
In which case take the last stage when all is looking good for a landing and not before.
Nevertheless its a big chunk of drag like an air brake and should be regarded as such pop the air break section away when you do not want that drag.
again its energy management which is not fully taught and knowing your aeroplane
Pace