How we complete our guild Challenges (7/7 Dungeons), rather quickly!

This is really a horde only method however using an Alliance dungeon will work just as well, although Im not sure of level requirements and what not.

1. Have yourself and 2 guild mate make some new characters
2. Level them up to between 15 and 21 ( I think this is the level bracket)(You can lock exp at this point if you want)
3. Log your main, go into Ragefire Chasm and clear all the way to "Taragaman the Hungerer" (Make sure to have one of your lowbie friends form the group)
4. Log your lowbie character, join your friends group, and re enter the dungeon with your 2 low level friends.
5. 3 Man the last boss ("Taragaman the Hungerer"), this is very easy especially if you are all wearing heirlooms.
6. Guild challenge complete, leave and reset the instance, rinse and repeat.

We usually have to do this in 2 separate occasions, because of the 5 dungeons per hour rule, OR do 5 then queue up in the LFG tool and do 2 runs. The whole process takes us less than an hour.
The dungeons don't have to be random, nor heroic, as long as they are level equivalent.

I hope this will enlighten at least some people that werent away this method existed. Many Thanks, and once again, apologies if re-posted!