Personally I am working a lot on keeping my lower body still in the B/S and thinking of turning down into my feet ( see other thread ) with my upper body. I like to think of the beach ball between the knees idea as a good one.

You want to keep your left knee from collasping in since this stops your hips from turning too far (buidling resistance and coil and thus the x-factor) and keeps you from swaying. It also shortens your backswing which for me is a good thing

So I too tend to set up with my knees a little bowed to help this feeling of keeping the left knees still. I find it really works for me so I would stick at it