Hey,
This only works with dungeons that can be set to heroic mode and you are too low for heroic mode's at that time.
So what you do is you are at location A and want to get to the location B. Now you know instance C is at location B. You queve to that instance and possibly run it throught (it's not needed) and you die. After you're dead and running leave party and change party-instance mode to heroic 5man and jump to the entrance. It doesnt allow you to enter and that's why you just got teleported to location B.
So in short: Queve for instance on what location you would like to be, when in instance, die. Release and run and before ressing via running to entrance door, you leave party and change to heroic mode.
Sorry for my english. And hopefully this wasnt published to the community yet, if it's repost just delete this post..
Good luck!