Yep, that's indeed what it was. Recruiting for the show started last fall. They were mainly looking for alumni to perform. I was asked by a friend of mine, who herself was a fellow Tsinghua-ian, to join the group dances. Equipped with "Can-Do" attitude, I accepted. All of us are volunteers including the director and we had to pay for the dance studio usage, and costumes, etc. The practice actually started in the 1st week of November last year, and we did it every Monday night without a break through the holidays until the show on May 21.
Now, Mud does not get his alone time every Monday night any more.