I never thought much about it, but I've always fed mine after our potty walks - i.e. the morning potty and the after work potty. I'd just feel bad to make them hold their potty to eat first before going outside. Plus, the walk works them up for an appetite, I think.
Usually after they eat, they rest and nap - i.e. after they eat breakfast, I leave them and go to work so they nap for a while; after they eat dinner, all of us nap because I'm so tired from after work
