Better reinforcement of Moscow might have led to the capture of Moscow
You said: I interpret that as increased German focus on Moscow. Seems oddly worded.
What I was meaning was better reinforcement by Germany of the forces going for Moscow instead of distractions to the south might have led to Moscow being captured or at least sieged but the lack of forces in the south would likely have meant no oil and a threat from the south to move north and cut off the siege...
Well, taking much of the European USSR would've seriously reduced population or manpower to man weapons besides messed up the rail network needed to move equipment and resources.
They already took much of european soviet land and ripped up rail lines in retreat too.
the point is that the capture of a hub does not destroy the rails leading to the hub which can be used to supply forces trying to retake that hub. The Capture or encirclement of Moscow would not destroy the rails leading from the new production centres east of the Urals to the approaches of Moscow.
That's what I meant by "economic objectives."
They are only economic resources if they contribute to your economy... things like steel and oil and indeed tanks and components are considered logistical resources rather than economic ones.
Ploesti wasn't out of range but about as good as the reich could expect. If US bombers could reach Ploesti from North Africa, they or British bombers probably could've attacked Baku--had it been taken--and maybe Astrakhan if based in Iraq. Or maybe they'd be granted access to Soviet airfields, assuming the Soviets didn't have sufficient capability to plaster Caucasus oilfields themselves.
Ploesti was out of range if US bombers could not operate through Soviet airfields...
But the Soviets probably wouldn't have wanted to help them, so soon after Khalkin Gol, and when they still seemed potentially dangerous at the start of '41.
But that is the point... if the Japanese had more brains and less pride they could have simply approached the Soviets and said we want to buy your timber and oil and steel and a few of your tank designs and fighter aircraft designs instead of invading Khalkin Gol.
The Soviets weren't hugely trusting of the Japanese, so the Japanese could increase the chances of cooperation by offering to return some territory they took in 1905 to sweeten the deal. It was in 1945 that the Japanese approached the Soviets to negotiate a peace deal with the US... by then their pride was gone and their brains told them this was their best option of the time.
What they didn't know was that Stalin had already promised the US that the Soviets would enter the war in the Pacific at Yalta... the Americans were afraid that when the war in Europe ended they might get left with a war in the Pacific that might go on for decades, so they demanded the Soviets join the war effort there.
Of course for the Soviets they got a lot of lost territory back finally... the Kurile islands among them...
But in the case of Leningrad ideology played a role. Inasmuch as it was the site of the bolshevik revolution, the nazis didn't want to take it so much as destroy it.
Don't read too much into the symbolism of post WWII claims by the Germans.
The reality is that they split their forces into three groups, of which none of the three were actually powerful enough for the intended jobs... so the northern branch got the reduced role of secure and hold, while the south group got the priority of take oilfield and the centre group move towards moscow.
They needed all three groups but didn't man them up with enough forces to do their jobs and were constantly switching from centre to south and often took forces from other forces when things got tough.
In theory, from a purely economic point of view, assuming the Germans could've repaired or totally rebuilt from scratch, facilities blown up by the retreating Soviets, and keep them functioning in wartime.
They didn't need to totally rebuild... if ISIS can extract oil from oilfields in northern iraq and syria then the germans could extract oil from oilfields in Russia.
The oil sold would not be economic... it is not about selling it and making money... it is about getting it to tank forces and airfields to operate tanks and aircraft.
Because in an alternate scenario it would've gotten much higher priority for capture or at least encirclement than it actually did, whereas taking Leningrad wasn't even an objective.
It was not the objective because there was never enough resources/men/aircraft/vehicles for them to complete a three pronged attack into such a vast country.
To change the balance you would need to draw forces from one or both of the other lines of attack. In effect they dithered shifting forces from the centre group to the south group... as you say the smaller force holding leningrad was not some huge resource they could have taken troops from to have taken moscow with... it was already a skeleton force that had its guts taken to feed the other two lines of attack.
To have tried to encircle Moscow would have required pretty much the vast majority of the southern force to be diverted to the centre force... which would have pretty much given up all occupation of the south and probably risked a flank attack like a super stalingrad from the south to cut off the centre forces attacking moscow.
If the German panzers encircled Moscow and the infantry finally caught up to strengthen the ring i.e. establish defensive positions, based on experience they probably could've held back a relief attempt by Zhukov. The latter did well historically in December 1941 because the Germans were still attacking; they hadn't shifted to a prepared defense.[/quote]
They had been ordered to dig in and defend and were still pushed back.
The temperatures involved at the time made digging in the only sensible option... at minus 40 degrees in equipment designed for a summer campaign you do not want to be caught out in the open...