A day after the patch YoshiP came out with that letter saying they did not want to resort to server-only but they could lock it down if they felt conditions warranted it. Obviously they pulled the trigger. This tends to be the way they roll out new things if you've been around for years, not getting too restrictive at-first. Not always the best idea of course.
Regardless, they need to make instances here and in more areas of the game.
