Are you looking for a groove in the front or rear? The rear outfeed table doesn't need one but the table has to sit at the same height as the saw. The way it looks a board won't be able to get past the lip on the outfeed table. The miter gauge would never be used on anything as wide as a groove behind the table would allow. It's not a good idea to use an infeed table because you will be too far away from the blade and won't have as much control.