Speedy/Mynok: Making smaller pockets isn't ineptitude, it's smart in a number of ways: it economizes on force applied compared to the result, it's safer for the units involved and the units involved are probably closer to their supply line next turn. If you try a big pocket and it turns sour, your mobile units might be trapped 10 or more hexes from the follow-up infantry, which is a rather serious problem. Making smaller pockets close to the starting line will mean units are within fairly easy reach of supporting infantry.
There's also the "death by a thousand cuts" theory that both sides can use (most people seem to think it only applies to the way the Soviets wage war). After the initial pockets, pocketing about a dozen divisions or more each turn will quickly force the Soviets to be thin on the ground with divisions in some areas.
One thing I'd like to try in my next campaign is to focus all 4 Pz Cps in AGC into one massive hammer. This would have pro's and con's as I see it:
Pro's - ability to smash absolutely anything in their path. Ability to create a large big pocket.
Con's - would need a mass of infantry to cover it's flanks and rear. Soviet's could put a massive wave of divisions in this sector blunting it's effectiveness and not allowing flexibility of exploitation elsewhere.
With that many mobile units, the mobile units themselves could cover most of the flanks, as they could leapfrog through Soviet lines. As long as you can keep the battle reasonably fluid, it's certainly an idea that's worth a try. I have a similar idea that I hope I'll be able to share with the readers of my own AAR when I finally get my game with notenome to work (I seem to be more or less the only one with multiplayer problems, which is both a good thing for the others and a bad thing for me). Even a carpet wouldn't be able to stop that much concentrated firepower.
I was confused for a moment, as I thought you suggested moving all Panzer Groups/Armies to AGC, which would make for awesome gains in the AGC area, but more or less halt the advance of the other army groups.