At the present time, it is still too early to say whether this is a large-scale diversionary attack or the main effort.
Morning Report for 6 June 1944, German Command in the West
The only high-command officer who responded correctly to the crisis at hand was Field Marshal Rundstedt, the old man who was there for window dressing and who was so scorned by Hitler and OKW.
Two hours before the sea-borne landings began, Rundstedt ordered the two reserve panzer divisions available for counterattack in Normandy, the 12th SS Panzer and Panzer Lehr, to move immediately toward Caen. He did so on the basis of an intuitive judgment that the airborne landings were on such a large scale that they could not be a mere deception maneuver (as some of his staff argued) and would have to be reinforced from the sea.
The only place such landings could come in lower Normandy were on the Calvados and Cotentin coasts. Runstedt wanted armor there to meet the attack.
Rundstedt's reasoning was sound, his action decisive, his orders clear.
But the panzer divisions were not under Runstedt’s command. They were in OKW reserve. To save precious time, Rundstedt had first ordered them to move out, then requested OKW approval.
OKW did not approve. At 0730 OKW informed Rundstedt that the two divisions could not be committed until Hitler gave the order, and Hitler was still sleeping.
Rundstedt had to countermand the move-out order.
Hitler slept until noon.
Stephen E. Ambrose