This is one of my favorite piecing techniques. I use it for flying geese, Square in a square and any time I want that angle seam. I save the cut off triangles and sew them into HST. I used to save them all, even ones that made only a 1" HST. However, I am finding that I toss any trimmings now that make anything less then 1 1/2" HST (after squaring up). My time and sanity are worth something too and I think more then those little scraps of fabric.