IMHO, shared by others, is that things were good along tactical plans, operational detail (usually). Strategy, not even grand strategy, was usually very poor even without the interference of Hitler. Part of that failing was totally crap attention to logistics. Mobilization plans (like the ones the Germans had prior to WWI) were great but once you got beyond that it went to hell. Even if the USSR had collapsed more than it did in the initial months of Barbarossa the logistics for even things like food, clothing, fuel were totally inadequate - throw in ammunition, medical supplies, rearward evacuation, spare parts for combat damage (on top of wear & tear of vehicles from crap Russian roads), and even with even minimal Russian resistance the Germans have severe limitations. The Germans knew the Soviet road system was crap, they knew the Russian RR gauge was different, they knew they were going to have to rely on rail for a lot of shipments. Did they make rational plans to deal with this, no.