For most people, I don't think the assignment of a Use Year is terribly important.
It really only matters if people vacation ONLY during a specific time of the year and intend to keep doing so over the next 40 years. And beyond that, it matters only in relation to late cancellations.
I'd be surprised if there were a great number of people who have been burned by having a Use Year that might be considered "bad" in relation to their vacation habits.