Originally Posted by CoachStuartMcDougal
Stop focusing on what's moving back, and primarily what's moving forward. Controlling the positions of the low side arm through rotation will probably be wrong and worse be in a position, out of leverage that will do damage to the shoulders and provide no benefit to propulsion.
In short, the focus is to send the high side arm to its forward destination as you feel feather light pressure on the low side arm moving back - the vaulting, hold/grip of the water happens. It you snap the vault (by pulling) you lose the external forces of momentum gained from the hight side arm moving forward. Also "feather light" feel is subjective given the swimmer's experience, i.e your feather light feel can be my most firm feel.
And with this focus being said, this is also exactly why I like to concentrate more on the upbeat in the 2 beat kick ,not the downbeat .When you spear in to the water and focus on moving forward is the time your leg on the same side is on the upbeat, and as your hand reaches forward to the end of it's spear the leg is now poised and stretched through the toes keeping the body long and it also gives you a great feeling of balance because of the stretch of the upbeat leg as an extension of your core. Then the downbeat happens as you now focus on the opposite leg which is on the way to the upbeat and vice versa .I'm not sure if anyone feels this way but at least for me this feels best and more natural.