It is a bit of a counter argument - but quite a few people run multiple networks and people are still moving between networks.

There /may/ be a problem with swarming. There might not be.

The only way to be certain is to keep an accurate track of what was swarmed, what wasn't and what is corrupted.

It is way to easy for people to think they see a pattern where none actually exists (particularly when they are assuming the existence of that pattern).

Mark