I am looking for a way to enter multiple dates into a field without the form becoming too long.
This will be used by an old school bookeeper who needs the form to fit on one page.
If you don't need the field to provide a date picker, verify it's a date, or don't need to sort the dates in the table, you can just use a text area field, and have your form filler enter the dates comma separated. Otherwise you'd have to add multiple fields. However, you can lessen the space each field takes up veritically, by using the "Labels Left" option (in the toolbar).