All measurements comes with an associated uncertainty. In different points of the span there is also different uncertainty. What is the max that they will allow? How they will track the calibration? They will check before the grid the calibration status like the weight of the glider? There is a lot of room to cheat.

You are allowed to use an amount of energy from the batteries. Depending on the efficiency of the motor, controller, propeller is how useful is that energy. Here in Argentina we are building electric motors for the self launching system at half of the price of the European motors by reducing the efficiency only 3%. Imagine the cost of increasing it 1%.