I know a few people who have used similar techniques to get their horse to listen to them on the trail, the key is to make sure they know exactly what you're asking for because you've practiced it at home.
I had the same situation. I used the same re-schooling and it does work. Even when he gets a little silly we do a circle. It makes him focus on something else and when they realise their silliness leads to work, it is easier to control. When he is very silly or hot, we do several circles, smaller ones or even disengage. The amount of work depends on him. Grey is right, they have to know the moves BEFORE going out on trail.
I was having the same problem with my mare. Yes the circles, bending the horse did help and also a deep breath exhale and relax making sure you are leaning back a bit rather than having your weight forward. Our communication has improved a lot since we practice and I now look forward to our sessions.