It's the only time it's ever happened, and in 1993 we only played 20 games not the regular 22.
Probably a good thing too.
As enjoyable as the year was, by the end we were going like busted arseholes. We finished third, a game and 9% ahead of 7th - Geelong, who were flying home. Only three teams - Richmond, Swans and Bears - won less than half their games and we'd already played all of them twice (the amazing win against Essendon in Round 15 was the last time we beat anyone other than those 3). So the next two games would have been tough (in fact, in the days where the second half of the season just mirrored the first half, the next two games would have been Adelaide and Carlton - eventually 3rd and 2nd.)
Chances are, for all the excitement, high scoring and fun that season was, and still being on top with one game to play and finishing with the best percentage, had we played 22 games, there's a reasonable chance we'd have missed the finals.