Fascinating motor design. I wonder how much torque is lost using a hall sensor vs backemf. It is my intuition that backemf would be more precise than hall senso

Fascinating motor design. I wonder how much torque is lost using a hall sensor vs backemf. It is my intuition that backemf would be more precise than hall sensor, but I don't know much about motor design. Would it be worth adding circuitry to amplify the backemf signal?