I've been working on this farm for some months.There are a couple of exploits which make this profitable farm arguably the best farming spot in the whole of wow at the moment.
Essentially what you do is switch between burst of speed for movement efficiency and shadow step to bypass portals, thereby allowing you to access three levels of trash where the ordinary player only has access to one. This means you can farm the place more or less indefinitely as you don't have to worry about instance lockout. Also, to avoid having back to the start every time you finish a run, I've also explained how to use proving grounds to port to the start of this and other raids instantly.
Even on my crappy half-dead server I can make 6485G per hour entirely from vendors and items which sell almost instantaneously. That's about three times more than anything else I could do to grind gold in my situation.
If you inhabit a high population server, you can do a LOT better. For example, patterns from HOF drop regularly which commonly sell for 1K+ a time on other realms. 15K per hour seemed like a reasonable estimate.
Disclaimer: Ten runs an hour isn't trivial with this much trash to farm. It will some practice and a decent ilvl to do it fast enough, it is something of a challenge.
I do this on 10-man. Mythic raiders who want an insane test of their skills might be interested in trying it on 25-man, the gold would be fantastic I would imagine.
(I'm on record as having issues with the concept of Looted Item Value. If I used to LIV to assess the value of this farm it would probably be 100K+ per hour, but I don't believe that method of analysis is practical for most people so I haven't used any inflated numbers.)