Here is the last change Blizzard made which continued into Wrath:
With the next weekly Burning Crusade Classic reset in each region, all “pre-made” groups will again be allowed to queue for Battlegrounds.
Note that I replied in a positive way to that because I believe that people should be able to group in an MMO. I’ve remained passionate about this topic in any iteration of WoW labeled “classic” the whole time.
Since that time there have been many threads about individuals still getting matched against premades. 
While I understand why you made this topic I’m personally not going to speculate further even though I have my predictions (and sadly not ones, outside of like removing the sand running, that are good long-term changes for a game that should NOT be messed with) but if others want to share then that’s fine.