I found this site interesting:
http://www.happy-horse-training.com/riders-position.html
At the moment I’m probably guilty of being in either position 1 or 2, also possibly tilting too far forward, I’m trying to correct my position but with neither mirrors nor eyes on the ground it can be difficult, and having been drummed into “do not adopt a chair seat” approach, psychologically there’s a real barrier to overcome. But is the article correct?