Ohh finally something else than neverending turtle grinding at timeless isle..

I tried your method with one booster and 4 slaves at 85, and without looting anything you can complete the boss kills in the lost city in a tad over 2 minutes. 3 minutes in total with re-entering the dungeon with reset.

The EXP is awesome, I mean it's ~10 x 3 minutes, and your slaves have dinged to 86.. Also 10 runs rewards 10* 5* 36g at minimum, which makes 1800g / 30 minutes.

Thank god Blizzard have removed or at least eased a bit the dungeon reseting, since it seems 5 dungeon IDs per an hour -restriction is gone now..

-Beeq