From what I heard they only didn't open it up because of how hectic having three lines for opening would be, so they were waiting for summer to be over and evaluate whether or not it was needed. Same wdwmagic thread said they do call for single riders quite a bit but also said about it being to hectic for it. Shame really because I love single rider lines and wish world used them more
Seven Dwarves would be such a good one for single riders. I mean, it'd increase actual through put on one of the most popular rides.