Just did some a simple example for myself.
Using AKL Kidani, studio as an example.
Purchase 160 points at $110/point = $17,600. No financing, Paid in full to make things simple.
Kidani has 36 years left in contract.
Assume $1000/year for dues, that's $36,000. (again, keeping it simple) (current dues for 2010 are $4.949 per point, so this should be $791.84)
Adding that to the $17,600 gives $53,600.
Dividing $53,600 over 36 years gives $1488 per year. (I know that the $17,600 was paid up front)
Currently, 1 week for an AKL Studio, Sunday-Sunday goes for 73 points; so I can get 2 weeks in a year for 146 points.
Take my cost of $1488/year divided by 14 nights gives me $106/night.
A standard room at AKL currently goes for $240/night, and as you show, will increase.
My rate of $106/night is locked in for 36 years.
The only thing lacking in my calculations is increase in yearly dues - and the possible finance of purchase over the first n years.
When spread over 36 years, I don't see how even the increase in dues would overtake the nightly room cost, even your discounted $140 rate - although it may come closer to that with financing and yearly dues increases.