Its a good summary Steve, and I agree with everything youve raised. however, I should point out that with, or without Malta, Axis logisitics were severely compromised. certainly the loss of cargoes made Axis preparations just that much harder, but the main constraint affcting Axis supply wasnt just Malta, it was also the wodefully inadequate port capacities that they struggled with. The main ports were Tripoli, followed by a very distant second place Benghazi. All the rest, including tobruk (totally and hopelessly wreckewd by the time it was captured) were laregely irrelevant.
According to OKW Quartermaster estimates, Rommel needed 60000 tons of supply per month to undertake operations at a normal pace. He received, on average 56000 tons oif supply per month AT THE PORTS OF DISEMBARKATION. Two things, however conspired to undo him. the first was Rommels complete disregard for his logistics limitations. He just kept attacking, and advancing, lengthening his supply lines well past the danger point. A division that is mobile and advancing will consume an average of 400 tons supply per day, in periods of heavy action, whereas a unit in a static position, or in mopping up operations, could consume about 60-100 tons per day. Obviously divisions sometimes on the move and sometimes in heated fights will be somewhere in between, and obviously a division that has been gutted will have lower supply demands than one that is full strength. Conversely, I am unsure if that 60000 tons would cover the numerous support echelons, like Corps troops and the like. Pz Armee Afrika used over 30000 trucks at full establishment, which was more than the entire AGS provisions....for just 12 divs.
Infantry Divs (unmotorized) were about half those numbers. In the middle of 1942, the Axis had about a dozen division, plus their air force, and their rear area garrisons to worry about. 60000 tons was not enough especially with Rommel disobeying orders and attacking like crazy all the time.
If Rommel had not advanced as he did, and did not attack so constantly, one might think he would survive a little longer. perhaps, But again, by June 1942, there were simply too many troops in North Afdrica, operating at very long distances from the supply heads, at an unsusceptible pace of operational tempo, for this to ever be a front that they were going to win.
Most unloading occurred from tripoli, about 1500 miles from Alamein. Tobruk is 300 miles, whilst Benghazi is 600. If we compromise, and assume for the excercise the supply head to be Benghazi, then for every 1000 tons unloaded at the port, only 636 will get to the front....the rest is lost in the trip (not inlcuding enemy action. In point of fact, of that 56000 tons per month, after we take into account the DAF operations and acts of sabotage by the LRDG and similar, less than half that 56000 tons was making it to the front (most estimates are about 26000 tons). Rommel at Alamein had 12.5 divs, of which 8 were mechanized, and 4.5 were german. Italian Infantry were only about 60% strength, , so in German equivalents, there were about 9 divs feeding on that supply line, plus about 350 a/c (roughly the equivalent of about 3.5 divs in terms of supply demand). Thus we have 12 div equivalents feeding off that supply line, with a minimum supply demand, even in the static role, of about 12-1500 tons per day. That equates to a minimum of around 36000 tons per month just to remain effective in a defensive situation.....but in mobile operations that figure would multiply by about 4 times.
Malta was critical, dont get me wrong, but Rommels supply problems were not solely due to Malta. Even without Malta to impede the flow of ships, Rommel would still have foundered due to a lack of supply. And that was mostly due to the limited port capacities available to the Germans.