There area lot of people(of which Zetterling) who will object to G.Nipe ,because,what Manstein may have claimed : Citadelle was no lost victory for Germany .
From Germany and World War II (tome VIII) (German edition) P 171:
"Das Scheitern des deutschen Angriffes bei Kursk bedeutete innerhalb des deutsch-sovjetischen Krieges keinen Wendepunkt,sondern nur eine virtuelle Wende."
Rough translation :
"The failure of the German attack at Kursk did not mean a turning point in the German-Russian war,it was only a virtual turning point ."
For Hitler,Citadelle was only a limited offensive, to prevent and forestall a big Soviet attack .
Some people are even claiming that the big Soviet losses at Kursk prevented a collaps of the Eastern Front in 1943 and an end of the war in may 1944.
Hitler and his generals wanted 2 things :
1) Shorten the front
2) Weaken the Soviet mobile forces .