The problem is that if Germany could send much more latter - when it actually tried - sending close-to-desired at the time it would do any good couldn't have been more of a strain.
That Germany needed every single panzer division it could get on the Eastern front (along with other things) would be more reasonable if it wasn't for the fact that the difference to the situation in the East of supplying Rommel more generously is a relative drop in the bucket.
Two divisions out of an army of what, three million men? And this is going to make a difference to the Eastern armies as significant as how much more Rommel can do with them (assuming sufficient supplies)?
I find that aspect of Hatton's argument the weakest, though interesting to hear figures on the ports in the area (a more convincing issue, since the ports can't be increased).
And similarly, the lack of roads etc. between North Africa and the objective...this applies just as much in reverse (as in, from Egypt to Tunis).
Also, blaming Rommel for overextending things in Africa would carry more weight if Hitler had tried harder to keep Rommel leashed, instead of encouraging him just enough to cause problems without doing anything to address his needs or wants.
Its a problematic situation, but its not an impossibility.
From Cooper: "In November, for instance, only 30,000 tons arrived, compared to 83,000 tons in August. ...The following year, 1942, saw considerable fluctuations in supply. The best month was April, when 150,000 tons came across the Mediterranean; the worst was March, when only 18,000 tons arrived."
So "what is being sent (and what is arriving)" is rather relevant, not just the in-theater issues.