How does Pat Parelli teach the transition from two hands to one in neck rein development?

Pat Parelli's approach to transitioning from two-handed to one-handed riding is gradual and uses a specific bridging technique that allows the horse to learn the neck rein cue while still having the clarity of direct rein backup available. His method involves beginning with what he describes as the indirect rein or bearing rein alongside the direct rein — both hands on the reins, but when asking for a right turn, the right direct rein signals the turn while the left rein simultaneously lays against the horse's neck. The horse begins associating the neck contact with the direction the direct rein is also indicating. Over many repetitions, the horse starts anticipating the turn from the neck contact before the direct rein needs to act. Parelli then introduces a subtle reduction of the direct rein signal while maintaining the neck rein. The direct rein softens to a suggestion rather than a full ask, with the neck rein carrying more of the communication. The horse continues filling in the meaning of the neck rein from its history of association with the direct rein signal. The final stage is dropping the direct rein and working purely from the neck rein with the rein held in one hand. Parelli is patient about this transition and specifically teaches not to rush it — a horse that appears to neck rein after only a few sessions of bridging work has typically learned to anticipate rather than genuinely responding to the neck rein as a confirmed cue. He looks for consistent, soft response to the neck rein at all three gaits in multiple environments before considering the transition complete.