I like to do similar beers like this myself, most Belgian yeasts attenuate very well. If you mashed low and long 147-150F it should dry out well...however some saison yeast would ferment a rock down to 1.000.
I also allow my ferment to run 3-4 days before adding my candi sugar when the krausen starts to drop off a bit. It will pick back up fermenting and dry out. The key to a dry beer for me, is a lower mash temp, and leave it for about 4 hours. So I would say with your extract, thats pretty good FG.