Hm: this is debunked by the following
Hm, it may be because of the language barrier that we are talking past each other:
Of course, the Wehrmacht did not run out of fuel overnight, but they had
A) (scarce) strategic reserves - by the way, almost until the end of the war.
B) hydrogenation plants, which were subsequently greatly expanded.
C) a fairly effective system for managing the available resources.
Nevertheless, the front-line units had to be very strict with their fuel allocations, which then also influenced operational mobility. Manstein described this in connection with the operations in '41 before Leningrad, where fuel consumption in particular caused considerable headaches.
Moreover, the fuel management of front-line units is a complicated issue: When Rommel withdrew a long way after Alamein because of insufficient fuel for operative warfare, this was doubted by higher authorities: After all, there would have been enough fuel for the entire way back....
Rommel is said to have had considerable problems explaining the special logistical requirements of mechanised units in operational warfare.
Moreover, not all fuel is the same:
The navy had an increased need for diesel, analogous to the intensification of the submarine war. I can't say anything about the heavy oil requirements of the surface units, I don't have any data or sufficient knowledge.
The air force, on the other hand, needed the lion's share of high-octane fuel. By the way, one of the main bottlenecks was not the amount of fuel, but the lack of suitable additives.
In the case of avgas, the situation was such that in '42 the allocations to the flight schools had to be cut in the meantime because it was needed at the front. By the time enough was available again, the flying weather was no longer optimal:
As far as the aforementioned connection between increased aircraft production, rising pilot losses, reduced training and fuel shortages is concerned, this was a cycle that negatively influenced each other and finally took on a momentum of its own that could no longer be controlled.
Stilla has described the interrelationships of this downward spiral quite well
But before I get bogged down in "sideshows" here, BTT:
My actual intention, however, was to point out that the Caucasus offensive was significantly influenced by strategic bottlenecks in fuel and crude oil supplies.
This was due to the two well-known factors: the stalemate of the offensive in '41 before Moscow and the entry of the USA into the war.
Until then, it had been speculated that with the fall of Moscow the campaign was essentially decided.
This on the subject of OTL
The western oil supplies started in 1942 and the USSR did not collapse in 1941 .
IF in ATL had been the main thrust of the Wehrmacht in '41 in the direction of the Caucasus and this had led to the conquest/elimination of the Caucasian oil region - then a stalemate would have arisen for both D and the SU with regard to these sources.
Since we are in a hypothetical universe from here on, I cannot for the life of me gauge whether this would have occurred already in '41 or only in '42. (Nor can I see that this part has already been dealt with in this thread). Nor can I judge what military-strategic and political effects this would have had on the further course of events on the Eastern Front.
But the quite essential supplies via Persia could then no longer take place.