I know it’s not nice to make fun of authors who don’t understand signals intelligence but presenting such a distorted version of events really makes me sad for the people who rely on popular books instead of more serious works ( like the official history ‘’British Intelligence in the second world War’’).
Since I always like to get to the bottom of things I decided to check ‘’scientifically’’ if the Allies were correct in their pre-invasion estimates.
I got the Allied estimates of German strength from ‘’British intelligence in the Second World War vol3 part2’’ p814-824 and the true numbers from Zetterling’s , ‘’Normandy 1944:German Military Organization, Combat Power and Organizational Effectiveness’’ p28 ( very ,very ,very good book! ).
This is the result:
The estimate of 35.500 men is for the two unidentified infantry div and the Pz Lehr using the minimum strengths possible in the eyes of Allied intelligence(10,000 for infantry and 15.500 for Pz).
It’s obvious that the Allies correctly estimated the strength of the Armored Divisions.However they seriously erred when it came to infantry formations.German infantry units were much weaker than expected.
This analysis has only covered manpower.A more comprehensive analysis would also look into AFV and trucks for the formations in the West .That would require additional posts but I can give the reader a quick overview:
Regarding tanks the Allies did not know how many were in the West.Their estimates ranged up to 3,000 ! The real number was 1,891 on 10 June.
Regarding supply trucks ( the bloodline of mobile warfare) the Germans were in a pathetic state.Best source on the subject is : Russell A. Hart , Feeding Mars: The Role of Logistics in the German Defeat in Normandy1944 ,War In History 1996 3: 418.
According to that article the main reason is that logistic priority was not assigned to the West .So while new formations and tanks were brought in to counter the expected Allied invasion there was no similar increase in supply trucks.New construction was sent East and the formations in the West had to depend on the French rail network.Thanks to Allied airpower this arrangement didn’t work out so well for the Germans!
The role of intelligence during the planning of Overlord is supposed to be a great success. I think considering the information presented so far the results are mixed.
The Allied disinformation plan Fortitude is also supposed to be a huge success.I don’t agree with that assessment .By May ’44 the Germans expected the Normandy landings.That’s why out of the four operational armored divisions in the West ( 2nd Pz , 21 Pz , 12 SS ,Lehr) three are close to Normandy and only 2nd Pz close to Calais.
Of course that discussion will require a separate post.