Very interesting. I am going to check that out with all my seam rippers as soon as I start sewing later today. I am very confident that I can sew a seam that needs ripping without any effort at all. After all, I always do. lol
Seriously, I have never known what the little ball was for. I did wonder at times, but never even looked it up. Now that I have stated I will be sewing and most probably ripping, my sewing should go perfectly today. I'll post an update when I actually get to test this method.