Do you not understand that perception of a threat can be just as effective at shutting down action as a real threat?
Regarding this point specifically, yes I would agree, but I would counter that with the fact that BT was never stagnant for any significant amount of time, and thus would cast into doubt the correlation between realm size and stagnancy, because there are many other things that can shut down action, and indeed that *have* shut down action, creating stagnation in places that don't have any realm with any scope comparable to what Enweil had.
