In 1940, frustrated with the perceived lack of success against RAF Fighter Command, Göring was keen on infusing the fighter force leadership with younger blood. He perceived a lack of aggressiveness in the Jagdgeschwader leadership. The likes of Theo Osterkamp were the first victim of this policy, handing over JG 51 to Werner Mölders. Oesau was considered to be one such rising star. However, being a star and staying in Göring's favor required keeping up the kill rate and promotions were invariably linked to scores. According to Dr. Kurt Tank, the Focke–Wulf designer, although many of the younger generation were good flyers, they were unable to cope with problems of overall planning and broader strategic aspects. However, Oesau was one of the outstanding leaders ever produced by Luftwaffe fighter wings with the likes of Werner Mölders and Adolf Galland.