skies said: "As a teenager in NY, whose mom did let him go see Musicals on his own, and that was when the area was really sketchy, the original Pippin with Ben Vereen and Jill Clayburgh, and Mack and Mabel with Bernadette Peters."
You really did not miss anything with Mack and Mabel. As the audience left the theatre, you felt like you had just attended a funeral. It was a huge failure with a (subsequently discovered) great score.
As a teenager, you probably would have LOVED Pippin. To this day, I have friends who have never seen a performance of Pippin since 1975 because they did not want to spoil the memory of the original production. They were both in college at the time, and managed to see it several times, because it ran for five years.