That seems an odd nit to pick - the choice of optics is intimately connected to the size of the sensor; plus it's not even right. The size of the circle-of-con

That seems an odd nit to pick - the choice of optics is intimately connected to the size of the sensor; plus it's not even right. The size of the circle-of-confusion depends also on the degree of enlargement and viewing distance in the final product - i.e. what looks sharp when viewed at arm's length on a phone with a Retina display can look not-sharp when cropped and enlarged to 20x30 and seen up close.