Not a problem! I have been out of it for a while too so I didn't know it existed as well. Like Trokair told me with this tool its a lot easier to see the area.
I thought Grimrail Depot was interesting too, with the never ending loop of terrain that just flows out in the background and having the train not actually move. Its a genius idea, and it just shows that Blizzard is improving more and more with every expansion. I believe the first time we have seen this would be during the Spine fight of Deathwing. Albeit not exactly the same, but almost the same concept. This is definitely a more complex concept however.