For this point of the war there are two distinct 'professional' historiographies. The traditional school states that after lightning quick advances and a bitter but successful battle of encirclement at Smolensk, the Germans ran into supply trouble, paused and then shifted direction because Hitler is crazy. This is the narrative of most German generals, for example, and it has been widely accepted in the West.
On the other hand, there is a new school of historiography, whose main exponents are Stahel and Glantz, which takes the Soviet accounts of the war more seriously. This narrative states that after quick advances against surprising (but wildly uneven) Soviet resistance, suffering massive losses it could not sustain, the German advance stalled, failing to encircle the majority of Soviet forces at Smolensk or Kiev. In other words the pockets at Uman and Smolensk become 'consolation pockets', i.e. they were not the pockets the Germans wanted to form, but they were the pockets the Germans *could* form with the situation being as it was. The Germans, exhausted and with their striking power seriously reduced, now poorly supplied, began to suffer strong counterattacks by Western, SW and Reserve Fronts, ground to a halt, and the only viable alternative was to shift direction, which itself was a concession that two months into the war the Wehrmacht could no longer go where it pleased, an admittance that most German generals were not willing to make. That doesn't mean Hitler wasn't crazy, as a broken clock is still right twice a day.
The WitE playerbase has many players who subscribe to both theories, which means there is always bound to be controversy. To a large degree the question becomes whether you think the historical Germans over performed or not. Many players regard it as the base standard, the floor per say, and so think it perfectly plausible that the Germans could advance to even greater lengths than they historically did 'if they don't make the same mistakes'. Personally I disagree with this view, as do many others.