That's an excellent video! It's definitely different from what chicks do. I'm feeling more prepared alreadyI can tell you what I've watched with other peoples hatches but I've only hatched goslings as far as waterfowl personally. They're supposed to be very similar but goslings are actually a little more difficult and even slower. One tip I can definitely share it that if you see and external pip and you're able to see the bill the chewing motion is a way to identify that it is not yet ready to hatch. I actually recorded a snippet of my gosling assist last time to show the difference in a gosling that was ready to hatch and one that wasn't yet ready.
"I had a gosling that zipped half way and got stuck so I decided to open the air cells on both of the remaining goslings in the incubator. I felt this was a great opportunity to show the difference in activity from a gosling that is ready to hatch and one that is not. The gosling on the left has only just barely widened the internal pip through the interior membrane and the gosling on the right has turned in the egg and opened a wider section of membrane while zipping. The constant chewing you're seeing from the gosling on the left is another sign that it's still working on absorbing the yolk and blood.