Theoretically, the -1 deg wouldn't cause roll couple or knife problems once trimmed for level flight and assuming you didn't change the throttle setting. But I always give it the juice when I knife which would cause the plane to go out of trim and quite possibly become a handful of fish. Just for grins, once you feel comfortable with the plane, stick some washers under the front wingbolts so you get -1(If thats even possible on your wing). Then you'll really know how it would have flown.