There is a consequence of the retreat/rout mechanics though. If you deploy in a 3-2-1 model (ie 3 units on the front, 2 as an immediate reserve, 1 as a deep reserve) which is a fair reflection of reality then (assuming only one retreat route) if the front breaks, 2 of the units will rout (nowhere to retreat to) and only 1 will retreat normally.
That's not my understanding or experience. Units with only fully stacked hexes to retreat to will instead retreat 2 or more hexes and take additional retreat attrition.
If low morale (Soviet) they usually rout, adding insult to injury as this drops their morale even more. But as most rallied for my turn I still thought it's better to have fully stacked frontline. The Germans had to do a deliberate attacks of 6-9 divisions costing them huge amount of MP to clear a single hex (and due to command penalties for units from different corps, costing them on average 20% of their on-map CV values).
...which means they need more to do less and then you win :)
Are there still such things as low morale Soviets?
Probably best to employ various tactics according to circumstances. A thin front allows you to conceal your strength. Three lines of units, be they single units, stacks of small units, strong or weak, is just three lines of units to the other side until they break through the front to see them. By then they're already comitted to the attack. Can work nicely if you have units to burn and space to trade.
Multi-corps/Army combat seems to be beneficial if each HQ brings enough SUs to compensate for an often paltry CV loss. I wonder whether it works as intended.
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