As the bar breaks from the floor during the first pull of a snatch or clean it is imperative that you get your knees out of the way. This helps with a straight bar path(good) or the bar sweeping into the body(better). The bar moving out around the knees is, as they say, no bueno!
Knees out and back is going to be better than just knees back for most lifters. First, the glutes will be more involved which is always a good thing.
The biggest issue I see with the knees back dominated pull is it leads to the hips rising faster than the chest and a straight legged “stripper” pull.
This is going to put your balance more towards your toes instead of more towards your heels. You’re also going to have a harder time with the double knee bend and getting to a solid power position. All of this is either going to lead to leaving the bar out front or looping the bar and missing behind. In both cases you’ll most likely be jumping forward.
There are exceptions to the rule. Colin Burns comes to mind.
To the other extreme, Jared Fleming pushes his knees way out.
You will eventually find a pull that works for you but for most, knees out and back.
- Coach Taylor