The most simple answer is that yes, it's a plot hole. They can't be in the Anoat system because they were in the Hoth system and they didn't have a working hyperdrive, which was a pretty major plot point. George Lucas screwed this, and a few other things (like the 12 parsec Kessel Run) up because he was a movie director, not an astrophysicist, and people have been scrambling to cover his arse over it for years. Hence all the desperate theories and explanations offered by the hack writers of the EU novels which have been repeated so often over the years that they've become "canon".
The thing is, no-one cares when Arnold Schwarzenegger fires 3000 bullets from a 200 round belt of machinegun ammo, because it's just a movie. Star Wars, like Star Trek, attracts fans that aren't satisfied unless they can come up with a theory as to why his machinegun can get 3000 bullets out a 200 round belt. This can get taken to an extreme. Check out the Star Wars Technical Commentaries, by Curtis Saxton, a theoretical astrophysicist with way too much time on his hands.
Plus, it categorically proves that a Star Destroyer would kick the Enterprises' *** any day of the week.