Yes I know that Hitler commanded the armoured divisions in the
West, but quoting from my previous post, "Move their armour forward
full speed, and they'll be caught by Allied firepower and airpower
in daylight."
Lots of historians like to make that claim that the Germans would
have stood a chance had they advanced once word of the invasion
spread. However, to reach the beaches in time to prevent the Allied
setting up a beach-head, the Germans will have to move in daylight
as well as night. And thats where Allied naval firepower and air
supremacy will destroy the bulk of German armour before it can be
effective. Not to forget that the "Rail Plan" had knocked out most
of the bridges in the Normandy area.
As it was, the invasion was a close run thing, Monty got pinned
down at Caen, while the Americans were stuck fast in the bocage for
almost 1 whole month till they finally broke out after Carentan
fell. The terrain was overwhelmingly in favour of the defenders,
and had the Germans concentrated more defences in the area, I think
the Overlord might have gone the way of Dieppe in '42
Shotgun, the Germans knew they couldn't defend the entire coast,
thats why they required good intel to forecast the location of
attack. They believed Calais was the place as it was the shortest
point from France to England, helped by Allied deception which
placed lots of phantom units opposite Calais.
For a good read on the planning, buildup and the actual invasion,
read Stephen Amborse's D-Day and Citizen soldiers.