Did she specifically call it a longarm? Maybe she's confused about what a longarm actually is. Many, many quilters have DSMs set up on a table. That was my first setup - I had a Brother with a 9" harp on a New Joy frame. That does not make it a longarm.
eta: Remember Sherry Reynold's beautiful award-winning quilt, "America, let it shine"? She quilted it on a DSM, a Bernina with a 7" harp. When you look at the size of the quilt and the amazing quilting on it, your jaw will drop.
Here's an interview with Sherry about the quilt and her process, unfortunately the pictures are not very good.
http://www.quiltersnewsletter.com/co...700-OTCweb.pdf