I remember pettipants!

My daughter always has her five and seven year old daughters wear bike shorts under their skirts and dresses.

That brought back memories. I was taught to use this trick for darts. I had/still have a Singer Touch and Sew Model 645. It has the wind-in-machine bobbin. I would wind the bobbin thread, not cut the thread and then start the point of the dart against the thread. This is fun because you don't have to start on a fold.