Well, one solution to this is to have it show you the route in advance and have you confirm it (or even edit it first). If it picks an obviously suboptimal rout

Well, one solution to this is to have it show you the route in advance and have you confirm it (or even edit it first). If it picks an obviously suboptimal route, you know something's up. If Krispy Kreme is already on your optimal route, then too bad. Basically, as long as the thing doing the navigating is also showing your the route it plans to take, then it can't pull any funny business like this without you noticing.