In reply to CookieMonster_Climber:
Sorry that i can't give you figures on it. We sometimes call it the reverse water knot.
I have used this knot since about 1990, when I was introduced to it by Swiss ace Eric Talmadge.
At that time he said it was the "competition knot" and used in the World Cups before the Fig 8 became a standard knot.
It is used by quite a few people I know who are IFMGA Guides.
It is easier to undo after being loaded and way "cleaner" around the front of your harness. There are no extra bits of rope,knots etc and is great on sport clips for that reason.
It is quick, simple and easy to tie.
Whatever you use stick with one and you will make fewer potential stuff ups. I have more difficulty now when I have to tie a Fig 8 when at the climbing wall (on their top ropes) as I so seldom tie it myself.