To make a long (40 turn) story short:

The Germans must defend against both the northern and southern E/W road routes. Entrenchments and flanking fire (and use of terrain hopes to lure the Soviets into disadvantageous assaults). The Soviets strategy was initially to assault along both, but then to send the southern strike force northwards. One key is to avoid fighting the Germans on their own ground (several entrenchments), but rather force as many Germans to come to you. It is better to have to defend against the German southern force launching a flanking attack than to beat oneself to death against entrenched infantry all the while having 88L71 fired shells destroying one's armor from 2000m.

Airpower is also key here with the Soviets getting several excellent draws with the 3 AT factors. The Germans tried to mitigate by keeping SPWs in hexes with the Tiger II's and PzV's Also Soviet artillery started off slowly, but, once the Vodka warmed up, managed some significant attacks.

Soviet minor victory clearing the N. road. The cost, however, to the Guards and the Soviet tank park was atrocious.