Here it is so many years later and this thread verifies something my husband and I noticed in our teenage geese.
We're both trained for wildlife handling, have lots of behaviorist background, and have been befuddled by the sheer lack of information about domestic geese. (I found and have read The Book of Geese by Holderread, but there's so much missing!)
We have been careful with the goslings as they grew, trying to keep them used to us without being overly friendly. We wanted them to see us as caretakers and food bringers, but not flock. And it's, more or less, worked. This past week one of the goslings (They're 11 weeks old, so we have a ways to go.) started with the shivering and then chest bumps. Having watched them interact, and seeing the obvious "dominance battles", I knew this was not something I could lose. After I had successfully defended my status as Big Goose, I noticed the neck shivering didn't stop, but the other geese would also take part in the shivering from time to time. I couldn't figure out any commonality until my husband found this discussion this morning, after he had been challenged by our largest goose (and won in the same manner - simply gently controlling the neck so that the goose can't get away, no harm to the goose) and he had noticed the neck shivering before, after, and during the "battle".
As we, thankfully, aren't the only people watching domestic geese as they "goose around", I was curious to know if anyone else has had these dominance challenges, and how they settled them?
Thank you for putting my lingering doubts to rest. It's a relief to know that our goslings are normal, even if they are spoiled and try to bully the dog.