Al and I are building some bookcases for his Sister, from White Oak. Our glue up panels are just two 1" x 6" boards, so pretty simple. However, even using dominoes, there are always little fluctuations that need sanded flush. But working in Al's shop is always nicer than the equipment I've had currently or in the past.
This is a twin barrel drum sander. 80 Grit on the first drum, 120 on the second. This is automation at it's finest.