Apparently I haven't been clicker training Gary enough. When I went out to see him with my clicker around my neck, he grabbed it in his mouth. He'd never done that before. So, I filled up my pockets with carrot bits and pretzels (horses seem to like the Trader Joe's pretzels with sesame and they are the perfect size) and we headed out to practice. He was pushy with reaching for treats, and did not target on cue, so it looks as if we need to go back to basics.
That means that the treat goes into a bowl on the ground, so Gary remembers that mooching is not appropriate. We'll go back to targeting, where he touches his nose to my hand and help him to get reliable with his ability to follow my hand. This will help us with my goal, which is for him to be able to reverse while free lunging 'into' the circle, rather than his habit, which is to turn away.
What's the yoga in this? Samskaras. Samskaras are habits, and some habits are useful, and some not so much. We replace the habits that are not useful with habits that are, by practicing for a long time, without attachment to outcome. So, it's back to the clicker basics for Gary to re-establish those useful habits.