> Once the pallet fork unlocks the balance wheel, that wheel has to start spinning very quickly. This is why gears in the gear train have holes in them – it red

> Once the pallet fork unlocks the balance wheel, that wheel has to start spinning very quickly. This is why gears in the gear train have holes in them – it reduces their moment of inertia so that the barrel can accelerate them more quickly. I think that should say "unlocks the escape wheel", not the balance wheel.