Two Forms, Same Name - Which one is Used?

Question - a designer modifies her mail file design, adding a second “Memo” form, exact same name and alias as the existing “Memo” form.The one she added is first on the list - the second one on the list is marked as the default form for the database.

When a new document is created, it uses the correct default form. However, when an existing memo is displayed, it uses the second, “non-default” memo form.

Is this because it comes first on the list, so Notes just uses the first one it finds? The ‘non-default’ form also has a later last-modified date, don’t know if this has anything to do with it.