Must bread dough clear the side of the mixer using the hook?
Often, higher hydration doughs don't need to be mixed in a mixer at all.  However, when using a mixer, it is more important to get the hydration correct, than to have all of the dough come away from the side of the bowl.  I would say to use a kitchen scale to measure ingredients, and don't worry about whether or not the dough comes away from the side of the mixing bowl.