tenuki: There are also many tournament options which do not use vacations, so those might also be a good choice to avoid people who take advantage of them.

It has been suggested, and I was thinking Fencer liked the idea of possible having a limit of 5 automatic vacation days being taken in one span. (A person going on vacation can choose more then 5 days, but would only stop the auto-vacations from being used for more then 5 days).