In theory, it sounds like a great idea, right? Unfortunately, I don't think it worked very well in Reach. Almost every single user created map in Reach matchmaking ranges from mediocre, to downright frustrating. I cannot remember the name, but one of the maps actually makes the frame rate drop quite drastically when playing split screen, so much as to make the game almost unplayable. Not only that, but the level design is truly horrible, whoever thought Putting Wraiths, Revenants, Ghosts, and regular/rocket hogs all together in a cramped corridor based level was a good idea is beyond me. If 343 wants to make forge maps, that's great (Lockout remake, anyone?) but please, PLEASE, do not add user created maps.