@Axistiger13:
Another idea: What if they prepared the attack, but did not launch it?
Problem with this Axistiger, is that this would have been bad for morale. You cannot tell someone(the Germans) the are better than someone else(the Russians) then say: we cannot beat them. The Germans did believe they could best the enemy.
Otherwise, I think it is a great idea.
Worsham: I have been thinking on this, but have not been able to get out my maps. ( Have been busy with Gettysburg!).
Problem with withdrawing from the salient, apart from the morale thing again, is that Kharkov looms large. It cannot be easily abandoned after the great campaign to retake it.
I believe there could have been a shortening of the Southern salient as long as it did not compromise Kharkov.
Building up a reserve and not throwing tanks at minefields and anti-tank emplacements, is definitely the way to go. The Germans always cost the Russians dear when able to do this. (Both 42 Kharkov and 43 come to mind.)
And Manstein was the man to do it. Sacking him was such a bad move by Hitler.