With the greatest of respect. I believe that the difference in felt pull weight between front and rear triggers, has far more to do with the angle of force and the distence from the pivot to the moment of force (the finger) than differing sear release pressures.

With the rear trigger on a double trigger gun the trigger finger has to move the trigger in a more upward fashion at the same time as to the rear. The front trigger pivots more naturally around the pin. The front trigger is generaly also longer reducing the pressure needed to trip the sear.

Regards.