talen314: The disadvantage is that some games, even if no vacation is taken, can easily last half a year, or longer. (Depending on the game, move time settings, and whether it's a multigame match). While I can see that not spending more than a few vacation days is fine for the next few months, it's harder to predict a long time in advance. It's even harder if the tournament has more rounds, and you advance to the next round. I've had cases where there's a years difference between me finishing my last game of the first round, the my first game of the second round starting.

As for games with people that aren't active - those people either haven't set autovacation, or have already ran out of vacation days. Their games are likely to time out before the other games are finished. It's only a problem for tournaments starting in January, where people have signed up long time in advance.