Everyone who has a horse will have experienced that feeling, when teaching them something new of them suddenly and completely getting it, even offering it and it feels smooth and easy. I'm thinking of a moment when I asked Theoden to move over laterally with his front and back legs at the same time. I normally ask him to do something three times and then change the subject before coming back to it. It's not unusual to come back to it only to find that the points have changed and he seems to have completely forgotten how to do it. This is not resistance, it is instinct. His automatic, instinctive, non-thinking reaction to the gentle leg aid is to push into it rather than to move away from it. In order to do the opposite, he has to shift the points in his mind, in other words, to really THINK. Once he has done that he can offer the movement again and the points shift gets easier and easier each time.
Thinking that the failure to comply with an aid is resistance is a resistance of our own to the fact that horse's have instincts. Other examples would include pulling on the bit if they feel a pressure, hiding their soft side when experiencing human touch for the first time, pushing forwards when they feel a pressure on their chest and so on. To help the horse shift the points himself we need to give him time and space. Thinking about what it is you want him to do can give him this room. Imagining Theoden's legs moving across is often all it takes to help him switch.
