From the web page: “This pattern requires 22-23 ounces of any color 4 ply yarn. Differences in yarn thickness, hook sizes used, personal tension and the number of “groups of 3 dc” will vary the shawl width. Make sample swatch or measure your shawl width after stitching the second Row 4. If necessary, rework piece to achieve your desired width, minus edging, making adjustments for all the variables before you continue to stitch. You may wish to change hook size or number of chains/groups.“

Another name for this stitch is the block stitch.