One of the things you can see in this video is how his hand direction is coming across the center on the entry which is causing the swimmer to go wide. The swimmer is going into a side to side movement which is causing the legs to splay at the back. When legs splay, it causes extra drag and resistance. How do we correct this?
We want to make it like you are swimming down a very narrow corridor. You need to tighten things up a little bit, narrow things up so you can just fit into that smaller space like you were swimming down a narrow corridor or a narrow hallway, then you’re going to be more efficient.
What we’d like to achieve is, make it feel like you are almost bringing the arm over more and so with your elbow and deltoid. We want to get that armpit more open as it comes over the top, so you may need to come over a little higher with the elbow even come over a little higher with the hand just to open that up and then on the entry.
You can see the fingertips are facing across the body, we want to get them facing forwards on the entry. We want to avoid those fingertips tracking across the center, we want them to face right out in front of the shoulder and then extend straight forwards out in front.