There are only two knots I use from tippet to fly... the Clinch Knot and the Duncan Loop or Uni Knot (for streamers). I'm not sure what the turle knot buys you other than it was designed for SKATING big flies (like Bombers) with heavy tippet on the surface for Atlantic Salmon where fishing below the surface is illegal. It's one of the weakest knots out there. There are better ones out there.