My attitude with moving forward is that say there's a branch about to fall on you..
Same here. I sometimes focus my thoughts/energy on the idea that the ground is going to collapse under us in a few seconds, so we move NOW. It seemed that it helped him to understand the idea, too. When I say move, then it has really, really good reasons. And recently it saved us both from possible injuries, when he spooked under saddle from a dog that appeared suddenly in the arena, jumped out of it on the road (my bad, he jumped straight onto icy pavement, so I hesitated to use emergency brakes because I feared we might both fall), and then I saw a car coming straight at us from a turn. Just because he responds so good to my "MOVE, the ground is collapsing!!" cue, he did not freeze in front of the car, but leaped into canter, just as I had asked, the same second I had asked, thus saving us both. It was a scare, but it proved to me once more, how important it is to teach the horse to be really, really responsive.