Grand Encirclement of an army (or more) is difficult/impossible in almost any game. This game does give you opportunities, but they are somewhat random as they flow out of the command and control rule. If a russian army gets hit by command and control, it cant move very far (if at all), and might get outflanked.
Without it, the Russian can do a controlled retreat.
I have, on occasion, cut off a division trying to escape, mostly because it could no longer get supply from its HQ, and so didnt get any AP's...
As well, if you hit a unit, and retreat it, then have enough AP's to attack it again, there is a very good chance that it will Break (surrender) on that second attack....or at least Panic (and lose extra steps).
As for breaking through a line, trouble is, you have to attrition the Russians to make the line so thin you can burst through it....and in my game, Wallas is retreating before letting that happen.
We are big on disbanding units to feed into the main army. Probably me more then him.
Integrity is just the percentage size of the unit vrs what it should be at full strength, so a low integrity unit is a unit that has lost a bunch of strength. There is something to be said for keeping your integrity up, as I am pretty sure units are breaking when they reach a certain low point. If you can keep their strength up, then they won't go "poof" in combat. Best source of replacement points is in your units, on the map...so rather then let those low integrity units die, giving up 8-12 strength points up because of a retreat result, disband them and let those points bolster up the units that are at 75%...to keep them fighting.
The only PP cost I can think of that may enter into this is if you decide to build new units. I believe Wallas is doing that by disbanding tank brigades and motorized brigades to build Tank Corps...which is sort of what they did historically anyways...
Not sure if the experience resets or not, but I suspect that the higher quality disband replacement points will help the replacement pool raise up in quality with the incoming trainee replacement points. So you may lose the 30 experience guy, but the umm 20? experience replacement points that enter the pool will become 25% with an equal amount of disbanee's entering.
“My logisticians are a humorless lot … they know if my campaign fails, they are the first ones I will slay.” – Alexander the Great