If teaching is really valued, and the Dean wants everyone to be around all the time, can you pair the 4-1 and 1-4 requests with a specific student-focused service activity?
That is, could those folks be signed up to do something high-profile that would benefit from their increased availability (e.g., run the student tutoring centre, do targeted outreach to high school students, start an experiential learning program)?
If the point is really to focus on research during the low semester, then taking on a huge new responsibility of any of those listed kinds negates that benefit and would be quite annoying because a semester isn't enough time to get any of those things off the ground or even become proficient in an already existent program.
If the faculty want more time for research, either they have to buy their way out of a course or they can make arrangements like Hegemony proposes because teaching multiple sections of the same prep of something one has taught before is a much easier load on the instructor, yet still fills the department's needs. Maybe it's because I haven't been privy to discussions in large departments, but around here, there would be no possible way to make a X-0 or a Y-1 plan work because certain classes must be taught every semester and we just barely have enough people to cover them.
