When doing my SAS I used the templates since I've never tried paper piecing. When pinning points together I was more concerned with lining up the points than the 1/4" seam allowance. I had to remake a few blocks that were just too far off to fudge together. I don't recommend "rounding and trimming" with this block as you will lose your points.
I'm glad to are having better success with PP and not wasting all your precut fabric.