As this phrase, as it stands here, is to my knowledge right, it does not apply to the spitfire. The spit had cranked wings with a reduced angle of attack at the outer parts of the wing (where the ailerons were). This meant that if, for a given speed, the angle of attack became too high on the inner section of the wing to generate lift it was still small enough on the outer sections. Hence while the wing stalled first on the inner section it stalled later on the outside section.

This was a security measure installed by supermarine because they were aware of the problem of the elliptical wing that you just mentioned.

When you read raf pilot accounts they repeatedly mention that they got buffeting shudder on the brick of a stall warning them about an imminent stall. This situation occured when the inner section stalled but not the outer section where the ailerons were, allowing the spit to be still controllable around the roll axis.

Of course cranking the wing also meant to deteriorate the aerodynamical properties of the elliptical wing so that it was less optimal aerodynamic wise. The induced drag was hence bigger than with an uncranked wing. As the advantage of the elliptical wing was later found to be minimal with respect to a trapezoid wing it was abandonned in aviation as the disadvantages in terms of production outweighted its minimal benefits. That's why I definitely think that the elliptical form in itself had nothing to do with the great performance. What supermarine however probably managed to pull off was to design a wing with a large surface which however created more drag but allowed for high lift which was still light weight and in particular very thin.