MMO's by nature exist for and are directed at MULTIPLAYER. To take away the ability to group up with a substantial amount of players, friends, etc, would be to gravely hinder the entire purpose of this game. Good boats sail well and good MMOS do multiplayer well. Thus, the removal of premades would objectively make swtor less of a good MMO. Additionally, as has been said by many posters above, if you don't like premades because you lose, take it as an opportunity to improve. Even more importantly, as an opportunity to make some friends or grow closer to a guild community.