One of the things that skews our discussions on this topic is that experienced players are often good enough to beat the AI with minimal losses.
To give you an example, my first game as Germany in LaR, I lost about 200,000 men against the Soviets before the Soviets capitulated. But I lost 300-400,000 men against partisans in France and the Balkans between the Fall of France and the beginning of Barbarossa. So, from the perspective of my first game as Germany, the partisans were a bigger drain on German resources
than the entire freaking Soviet Union.
In that situation, what would you optimize?