So, this is sort of an interesting move. They were already selling guaranteed weeks. (Old-fashioned time share vs normal point system.) And you can still trade your guaranteed week back in for points. However, as I look at it, the ONLY real benefit to this is that you can pre-book 5 people in the race event. But is this really a problem? I mean, I know these events fill up, but doesn't it take several weeks to fill up?
While RunDisney events are very popular with DVC members, MOST of the bookings seem to be not full week bookings, but more Thursday to Sunday bookings. We are travelling the week of the Princess half this year, and while everything was booked at the end of the week by the 7-month (general booking) window, we were able to snatch a Boardwalk view room for Sunday - Thursday before the race with no problem at all, and that's a pretty popular room category.
Overall, I seriously doubt that this sells a lot of DVC...spending $30,000 to get 5 guaranteed race spots? Though there may be the occasional person that this pushes them over to edge to buy.