It will be some time before Adelphia systems are converted to the TWC billing/control system. That system is complicated in my opinion. And until then, TWC does not have simple control of the boxes, authorization, billing, etc. of Adelphia systems. Remember, they are running TWO separate, and mostly incompatible cable systems. The integration will take months, and the plant upgrades in many areas will take years. Some areas of Adelphia were complete junk. Some of their old line extenders are the size of fiber nodes today and some areas are not even two-way. Really, really outdated in some areas.
As far as capacity goes, yes, cable does face some issues. Not as much as satellite in my opinion, because cable can and will do Switced Video Broadcasting which is very, very similar to what Uverse is doing. Only sending the channel your box requests to your house, instead of the whole lineup at the same time--hogging up bandwith. Last I checked, DBS can't do that. : )