Remember the days we didn't have rollover? There are hundreds of ways MR could have augmented the program and what they did is a lot better than nothing. Unfortunately, they are not committed to this plan by having to renew it's implementation each year instead of making it a permanent addition.
It is a loyalty program so they want to encourage you to continue using their product. For those that don't make top tier each year, now has a means to reach it by combining two years to gain status. Those that do make top tier has a means to accelerate their lifetime status with the rollover nights counting double for that goal. I think they found a good mix to accomplish what they want.
Of course I would love to maximize my status with minimal stays, but they didn't ask me how I would build the program.
