Relative combat efficiency - Normandy 1944

[Kingfish]

the post-Overlord plan called for the allies being on the Seine by D+90. That doesn't suggest the allies envisioned a collapse in the German front line.

They never expected a front line in Normandy. The thinking was the Germans would, after failing to repulse the landings, withdraw in good order into the interior of France using the main rivers as stop lines. The German attempt to hold the Allies in Normandy accelerated their demise.

Agreed, a gradual withdrawal in good order over a period of three months doesn't square with pintere's claim.

[Gooner1]

This argument is missing the critical context that these “fresh” divisions, apart from their often unfinished state, or that they were sometimes only battlegroups, also served as a substitute for casualty replacements. The large bulk of casualties was not matched by replacements, because at the time of the Normandy battle, the Germans were facing their yet greatest disasters and crisis on the Eastern front. So, seven or eight divisions were needed to nominally replace the 100,000 or so casualties not replaced by normal replacement personnel (disregarding for simplicity that these “fresh” divisions included a lot of non-combat personnel, while combat losses drained almost exclusively combat personnel).
A similar argument could be made for newly arriving armoured divisions, because armour losses in the already committed divisions were not replaced, either.

If you want to demonstrate that the Germans were weaker in Normandy just before Cobra than they were at the beginning of July, please do so.
German divisions, or some of them anyway, also received replacements in troops and equipment during the campaign. Not on the scale that Allied divisions but that wasn't their style. They preferred having more divisions. As it was by the end of August the Allies in North West Europe had engaged 51 different German divisions - they were not running out of troops.

In addition, there was not much alternative to sending the majority of newly arriving forces to the British sector. A breakthrough there would have cut off all German forces fighting in Normandy,

How, where is the second 'pincer' or the anvil to the hammer?

[Sheldrake]

German doctrine demanded that the commander made a choice about the point of main effort, in defence as well as attack.
The Germans own logic dictated that the Western Sector would be the weaker. A thrust South East from Normandy posed a greater danger than a thrust South from Coutances. This was the gist of the Allied plan.

In the event I don't believe a thrust in the Eastern sector could have been a greater danger. Assuming there was one where would they go, West to cut-off 7th Army or North East to Paris? Either way I can't see it being as deadly to the German army in France as the actual breakthrough and 'right-turn'.

Moreover, and as has been noted, since most German reinforcements would arrive in the Eastern sector first, any breakthrough there would inevitably encounter those fresh units sooner than they would in the West.

That is not how the Germans saw it, nor how the Allied commanders predicted how the Germans would see it. A drive to Paris would cut the German supply routes, painfully dependent on rail and hampered by destroyed bridges. If the Allies were established between the Seine and Loire all German forces to their West would be doomed.

[Mori]

The Allied plan was based on the assumption that the Germans would reinforce the East rather than West sector. Montgomery had studied the German approach to war. The picture of sometime Kreigsacademie instructor Rommel in his caravan was not a mere affectation. German doctrine demanded that the commander made a choice about the point of main effort, in defence as well as attack. The Germans own logic dictated that the Western Sector would be the weaker. A thrust South East from Normandy posed a greater danger than a thrust South from Coutances. This was the gist of the Allied plan.

The key ground in the Normandy beach head we3re the portsd, of which the Germans knew about Cherbourg. Rommel knew that the Germans shouldm attempt to strike the Americans before they captured Cherbourg, but his efforts were pre-empted by 2nd Army attacks which gav ethe Germans no opportunity to regroup.

Yes, that's another way to explain the same thing: the Allies attacks denied the Germans any opportunity to build reserves / counter-strike. It was not fundamental where in the front these attacks would take place as long as they would force the Germans to commit units against them.

Cerrtainly, a breakthrough in the East was more annoying: closer to Paris, and through flat terrain instead of bocage. But this consideration was, in my opinion, secondary. What mattered first was the above; never let the Germans any opportunity to regroup.

I read that Rommel first wanted to counter strike on the West, and had some plans to do that a few days after the invasion. These plans were cancelled, and it looks like applying them would have been quite a disaster for the Germans. Germans would have move units from East to West right before a British operation...

[Mori]

While the historical outcome supports the above, I am not convinced this was designed in the way you described. IIRC, the post-Overlord plan called for the allies being on the Seine by D+90. That doesn't suggest the allies envisioned a collapse in the German front line.

You have a point about the risk of explaining history with hindsight.

That said, I would not confuse the assumptions used for logistical planning with the operational conduct of the battle. The D+90 line, if it had any value, was for logistics and supply. (By the way, I'd love to know whether it was actually used by services preparing supplies, ammunition, replacements etc. Can't remember a history od D-Day investigating the point, but the answer should not be difficult to find in the US/UK archives)

The operational way to conduct the Normandy battle was really as explained: attack everywhere to deny the Germans any opportunity to create a reserve, and use them until they have no choice but to retreat en masse. That's what Montgomery keeps explaining in June and July, and that's why he is so confident the battle is going all right even if the front line does not move much.

Note that exactly the same thing happened at El Alamein: the 8th army destroyed the Axis without having to surround them.

[Aber]

To clarify, I assume by 'attack everywhere' you do not mean 'attack everywhere at the same time', but staggered attacks in different areas to draw in any German reserves.

I absolutely agree with you on hindsight; eg Normandy would look very different if the Mortain counterattack did not take place, the narrative of Market Garden would change if the Germans managed to blow the bridges at Nijmagen, and any delay to the Battle of the Bulge might lead to an earlier falling out at the CCS.

[Michael Kenny]

Pre Invasion expectations. Phase line. Poor copies but readable

[Sheldrake]

Pre Invasion expectations. Phase line. Poor copies but readable

Phase LinesD+25.jpg

Phase Lines .D+40.jpg

Phase Lines . D50-D70.jpg

Phase Lines .D70-D90.jpg

Interesting. I have not seen those before. Obviously US First Army. What is the source?

The British story is that then phase lines were to give the logicistians something to use for planning purposes. Carlo D'este discusses the planning process in some detail. Anyone can draw phase lines, but they are meaningless until the enemy has had their say.

One feature of C 20th warfare is that the defender has the choice of positional or delaying defence. They can stand and fight, trading casualties in a battle of attrition, or give up some some space. Their call, not the attackers.

[Michael Kenny]

Some obscure paper on the internet. Did not keep a record.

[Kingfish]

One feature of C 20th warfare is that the defender has the choice of positional or delaying defence. They can stand and fight, trading casualties in a battle of attrition, or give up some some space. Their call, not the attackers.

Not the attackers?
Isn't it the goal of the attacker to shape the battle in his favor?

[Sheldrake]

One feature of C 20th warfare is that the defender has the choice of positional or delaying defence. They can stand and fight, trading casualties in a battle of attrition, or give up some some space. Their call, not the attackers.

Not the attackers?
Isn't it the goal of the attacker to shape the battle in his favor?

The attacker decides when and where to attack and with what, and whether to continue attacking.
The defender decides whether to stay and fight.

[Aber]

Some obscure paper on the internet. Did not keep a record.

This?

http://www.history.army.mil/documents/w ... /g4-ol.htm

OUTLINE OF OPERATION OVERLORD

[Note: This manuscript was prepared by the Historical Section of the G-4 of the Communications Zone, European Theater of Operations (COMZ, ETOUSA) as volume seven of its multi-volume manuscript organizational history. It was subsequently deposited at the Office of the Chief of Military History (OCMH; now US Army Center of Military History) for reference use by historians preparing the official history of the Army in World War II. It is typical of the kinds of detailed studies routinely acquired (as in this case) or carried out by the deployed historians during World War II. The original is on file in the Historical Manuscripts Collection (HMC) under file number 8-3.4 AA v.7, which should be cited in footnotes, along with the title. It is reproduced here with only those limited modifications required to adapt to the World Wide Web; spelling, punctuation, and slang usage have not been altered from the original. Where modern explanatory notes were required, they have been inserted as italicized text in square brackets.]

[Kingfish]

One feature of C 20th warfare is that the defender has the choice of positional or delaying defence. They can stand and fight, trading casualties in a battle of attrition, or give up some some space. Their call, not the attackers.

Not the attackers?
Isn't it the goal of the attacker to shape the battle in his favor?

The attacker decides when and where to attack and with what, and whether to continue attacking.
The defender decides whether to stay and fight.

If the attack is successful the defender no longer has the luxury of deciding. The attacker has made the decision for them.

[Michate]

If you want to demonstrate that the Germans were weaker in Normandy just before Cobra than they were at the beginning of July, please do so.

I have not said that they were "weaker", and do not think so, on an absolute basis. I think however that a reasonable case can be made that in relative terms (i.e. in comparison to the Allied strength development), the Germans were weaker at the end of July than at the beginning.

Otherwise I have just stated the obvious, which your simplistic division count blatantly ignores, that the large majority of the casualties the German forces already engaged suffered, were not replaced and that therefore part of the divisions newly sent to Normandy were needed just to maintain combat power.

German divisions, or some of them anyway, also received replacements in troops and equipment during the campaign. Not on the scale that Allied divisions but that wasn't their style.

It was not a question of "their style", it was a question of a very desperate situation, with manpower strained to the limit by the situation in the East, which constrained replacements to a trickle compared with a flood of casualties, so the Westheer had to replace them by consuming its own substance.

--------------------------------------
For instance, army group B weekly report for 10-16 July 1944, dated 17 July 1944:

Casualties suffered in the West for the period 6 June to 7 July 1944: 100,089 (including 3,791 Russians)
Replacements sent: 8,395. In addition replacements promised, but still not sent: 5,303.
----------------------------------

IOW, more than 90% of casualties had not been replaced.
If we may assume, just for simplicity's sake, the number of combat effectives (those "at the sharp end" who suffer the casualties) in a contemporary German division as 6,000, than no less than 15 divisions would have been needed to replace those casualties.

--------------------------------
army group B weekly report for 24-30 July 1944, dated 31 July 1944:

Casualties suffered in the West for the period 6 June to 7 July 1944: 127,247 (including 3,806 Russians)
Replacements sent: 14,594. A further 8,000 replacements were gained from dissolving the 165. Reserve Division (already part of the Westheer), as the previous report states.
--------------------------------

IOW, the situation hardly improved.

How, where is the second 'pincer' or the anvil to the hammer?

No second pincer would have been needed. A (hypothetical) breakthrough in the Caen sector, followed by an advance to the South or South-East would have cut off the German forces to the West of it.

[Gooner1]

Pre Invasion expectations. Phase line. Poor copies but readable

Phase LinesD+25.jpg

Phase Lines .D+40.jpg

Phase Lines . D50-D70.jpg

Phase Lines .D70-D90.jpg

From David Belchem 'All in The Days March' (1977)

"The fact is that the phase-line map was not drawn by Montgomery's planning section, of which I was in charge. It was produced as a cockshy* by our American colleagues, because their staff planning procedures demanded such forecasts when deliberate offensive plans were recorded. All I ever personally said in this context was that Montgomery had told me that he hoped to reach the line of the River Seine by D+90, but that this was not a definite forecast nor were we to take it as anything more than a general guide. "

'* a target aimed at in throwing games' http://www.collinsdictionary.com/dictio ... sh/cockshy