There are a couple or more of other reasons to shorten the Masters class.
1. Judging load on other pilots. I'm way too old to enjoy spending over half my time at a contesrt watching the large class of Masters flyers fly a long sequence. (And not judging take offs and landings in Masters class would give judges a little break between flyers too) Makes me want to fly Masters instead of FAI so I won't have to judge them.
2. It's not really fair to the other classes that Masters takes up a much greater percentage of the contest time.