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GitHub User: Subtletree
It actually does, but since it becomes unstickied it moves down the list.
The link_to_add_fields helper is called server side before the page is sent to the client.
If you look at the link_to_add_fields helper you will see that it generates a link_to at the bottom. This is the link that the client clicks on, not the link_to_add_fields helper method.