Let me start by saying that I don't have bad form and am not looking for a major form overhaul. One flaw that has been pointed out to me is that I do not extend my left arm in the opposite direction of my right arm when I am in full pullback. This probably doesn't fully open my shoulders. What are the results of not extending the left arm in the pullback? What will happen if I do begin extending it out?
For references, there's a video of me throwing an airshot and another of me throwing a roller if you click here
. My left arm leaves my body a little bit, but nowhere near as much as most of the people who have technique videos on this site. However, some people (Cameron Todd, Avery Jenkins) have very similar left arm motion to me.
So, should I start incorporating more extension in to my throw? What will be the benefits? And what side effects will show up?