I thought gravity point had a small radius? The ships are relatively far away, about a kilometer, so I'm not quite sure how Gravity Point is accomplishing the monumental movements described in the post. I mean, arguably, it could be moving the chains closer to the point you chose but, again, with the small radius it wouldn't have that much of an effect on these hulking Skyships which are a good distance apart. Certainly it wouldn't make them almost plummet into each other if my reading of the description of your spell on the CS is correct.