When you lead her, and I emphasize giving her 4' of lead, your are focused ahead. Suddenly flap your elbow up (think chicken dance) as you walk. Do not do it so there is rhythm but keep it random. If she moves close she'll get a clip in the jaw. It will not make her headshy. Just keep walking toward your mark up ahead. Continue with the elbow flap. Once she's hit your elbow she's not in a hurry to repeat it. She's not "poor baby". She just got her comeuppance. If you hold the lead close to her halter, you set yourself up to get hit with her shoulder. It also forces her to walk with her neck bent toward you and she's invariably carrying the weight of your arm. With four feet of lead, she can walk her own path with a straight neck and only the weight of her head and not your arm. When you get this down pat, there will be parallel tracks behind you, hers and yours.