The way it worked -to my understanding, correct me if I'm wrong - is: The inheritance is divided more or less equally amongst the sons instead of falling to say the oldest or most able son.

This seems like a more just system, fair enough . But aren't it's flaws obvious? Wouldn't the land be to small to be used effectively by anyone's son after a few generations? Doesn't this create even more strife than it solves?

Perhaps I misunderstand something. Am i thinking too much of inheritance as land and this mainly meant things like slaves and weapons? Was population growth to slow to constantly create the problematic sitution discribed above? If it did was emigrating an option?

If not though conflicts like Karl and Karlmann must have been something common. Nevertheless it worked for centuries. So, again my question: How did this sustain itself?