No, both Saber and Arcueid were definitely drawn by Takeuchi. Takeuchi tends to draw breasts more "pointed", while Koyama's breasts are more "rounded". Takeuchi and Koyama both tend to draw noses a bit differently lately too. Takeuchi and Koyama also draw hair differently, with Koyama generally drawing more individual strands. You can also tell from the differences in facial structures; Takeuchi facial structures tend to be different from Koyama facial structures.