We've been members for 5 years. I understand how the 7 month and 11 month window work. I understand about how when they add inventory they sell more points, but I believe that there is entropy in the system, even though they sell more points, I think there would be more availability due to cancellations, or people banking, or whatever. Look at PVC, for the most part their higher priced studios are available longer than other inventory.
I don't think it is just a DVC issue, Disney is crowded! When I was looking for value resorts last October, there was NOTHING available and that was about 3-4 weeks ahead of the Saturday I was looking for. Yes, part of the problem is that my friend's husband asked me to look for something less than a month away from the date, and this year I already booked it well in advance - problem solved.