I have never knitted with lace weight yarn before. I just started a shawl using Kauni lace weight yarn. Although it is knitting up beautifully, the yarn is so thin in places that it breaks. I am trying to be very careful not to tug on the yarn. This has happened several times already, and I don't think I have the patience to deal with this problem throughout the project. Is this often a problem with lace weight yarn? Am I doing something wrong, or is the yarn defective?:?? I am making the Swallowtail shawl using size 4 needles, if that makes a difference.