22 January 1944: "SHINGLE was not a bad plan, and it embodied the military virtues of audacity and surprise. Yet enough pieces of it were bad to risk rotting the whole. The belief that Kesserling would ignore this spear in the ribs and withdraw to the north was simply wishful. 'It was a bluff, to scare the Germans into pulling back,' Alexander later admitted. No flinty-eyed assessment analyzed the likely strategic reaction of an enemy that did not scare easily. Once again, the Allies lacked the true measure of their adversaries." "The Day of Battle" - Rick Atkinson, page 327. Dave
Pretty much, and yet five months later they were surprised again by the same German reaction to NEPTUNE, expecting them to execute a planned withdrawal to the Seine and then German frontier after the beachhead was established. Over and over the Allies failed to assess the full measure of German desperation and resilience.