If people could do it in older patches, what makes you think it is not achievable in the newer patches where the max level gear obtainable is on a runaway from the actual difficultly of the dungeons?

One of the examples of unconventional party make ups: No healer - 1 tank 3DPS Brayflox HM full run completed in 7:55

https://www.youtube.com/watch?v=aRnkWpx8F3c

When your DPS clears trash fast enough, it works.