I looked into this once, and they .... just don't worry about it. Each generator just matches whatever it sees. If you are trying to match two other generators

I looked into this once, and they .... just don't worry about it. Each generator just matches whatever it sees. If you are trying to match two other generators (like in a triangle, and due to the speed of light it's impossible for all to be perfectly in sync), then it matches to an average of the two, and apparently that works.