I heard this information before when I purchased my Bernina. IMHO they just wanted me to buy more thread. Not only did it not make a difference....it was a real waste of thread. Especially if you are embroiderying and using a lot of different colors, I thought. So......I did NOT cut the thread and pull down through the needle. Yesterday I paid $30.00 to have the shredded thread and lint cleaned out of my 830 Bernina. I LEARNED MY LESSON!!! I now pull the thread down through the needle as I was told. Funny the tech that fixed my machine knew exactly what I had not been doing. The machine would stitch 8 or 9 stitches and then stop. Fortunately I could turn off the sensor and finish my project, before taking my machine in to be "fixed".