While this may not be an effective way to abuse a trade route I have seen it abused to avoid fighting. Chasing an enemy while they just fly into the invisible wall. The person being chased just wasted time and RP by flying into the dead zone. Now the ship that flew into the wall gets a fresh ship at its original point of origin and doesn't lose anything. It may not be a big problem but if you've ever chased someone to the wall.. it is most annoying.