Originally Posted by Mountain Bronco
It adds at least a week to the season, which is another way of adding games without lengthening the regular season so it is a cute way to avoid that issue.
Adding 4 teams to the playoffs actually wouldn't lengthen the season at all. It would just eliminate the Bye week for the top two teams in each conference.
It would mean 4 more games during the first round, but not an extra round.