Tanks arent supposed to be static defensive weapons, but breakthrough and mobile defence weapons.
Problem is, dude, that tanks are not even really effective at that. I have had similar experiences as ljigsrb when attempting to "break through" a relatively flimsy defense.
I typically have three medium Panzers with 1 inf brigade, 1 hvy armor brigade, and 1 engineer brigade attached, and usually at least 1 motorized infantry division with either anti tank, aa, or armored car attached. Yet I have had multiple ocassions where such a configuration at full strength and in full supply cannot "break through" a half dozen or so infantry brigades in the USSR.
What I have found the armor to be extremely well suited for is racing around the map and capturing key provinces and painting the USSR gray once my INFANTRY punch gaping holes in the Soviet lines and scatter their troops to the four winds in disarray.
With blitzkreig, it was the opposite. It was the tanks that punched through after a few days of bombing and artillery shelling, with the infantry coming along behind to mop up and hold territory.
Let me tell you, nothing sucks more than to have your armor, on which you have spent so much time and resources, stop cold in its tracks well before reaching the Urals because their ESE is as near to zero as a number can get and they have run out of fuel and supplies (even though I have multiple HQs in the immediate vicinity with all of the logistics research maxed out).
Then, the armor truly is worthless (which, I suppose, is fairly close to what actually happened to the Germans - but for very different reasons).
