I used travel mode to open up enough room to SPEC. It seems that the AI don't use travel mode. Once your relative velocity is above their maneuvering velocity, it seems that they start to SPEC to try to catch you. It turns out to be SPEC, fall behind, SPEC, fall behind, ad infinitum.
Expected behavior: A space battle in real space should be all about acceleration. When I went to travel mode, they should have done the same. If they can't match my acceleration then I should eventually escape, and maybe they would try to SPEC to keep up, maybe take a pot shot. If they match my acceleration, they should keep pace with me until I dock, land, or they get bored, maybe SPEC'ing in to get closer to shoot. If they exceed my acceleration, it is just like I am standing still and they are walking to me - eventually they will catch up and fry me. My only hope is to gain enough time to SPEC away.