All hooks/pulls/etc. have a maximum tether range which is usually a bit longer original ability range. If you're just moving to the other side of the target at the same distance away, you could easily have the first tug pull him one direction while the second tug pulls the other.
It might be easier to imagine with Fiddle's drain, since you often see the difference there between ability range and tether range. If you stay in tether range, you're good. If not, the ability just breaks on its own. Flashing is no different.