OK, so these knot tying instructions are hardly necessary since this knot is so simple! The main use I find for it is to prevent fraying near a free end of kite line, in just about any situation. Of course, for nylon or polyester lines there is also the old kite-maker's trick of melting the frayed end with a flame. The gas stove lighter can come in handy for this.

Another handy use is to fine-tune the amount of bow in a horizontal spar. Wait, I'll explain! The MBK kite designs use fixed-length toggled bow-lines to put some curvature in horizontal spars. To increase the amount of curvature, you can put knots in the lines. One at a time, until the amount of bow is where you like it. Actually, it's surprising how much difference just one knot makes!

I tried using this knot to prevent Slip Knots from pulling through, but it's not really big enough. A bigger knot like a small Loop Knot is much better, though it doesn't look quite so tidy.

Oh yes, one more situation... The shoe-lace ties used by the kites in the Dowel Series fray really badly where cut with scissors. A tight Simple Knot near the cut end of the shoe-lace is quick, easy and effective at stopping the fray. The specified length to make the ties takes this into account!