One thing I never do with a herd bound horse is let him pull me around or 'force him' to walk, or whatever.
If he wants to dance and jig about while on the line, because he is herdbound, fine, I will gladly oblige; I have all sorts of groundwork exercises up my sleeve that I teach my horses, or that I train to project horses, so it's not like I can't work that tail off, and get that focus back on me, and I always work them a little beyond the time they put their focus back on me...
If you are undersaddle...same thing; especially if he is pulling on you; one thing I absolutely HATE seeing is people forcing a herd bound horse to walk, or allowing him to move faster when he is going toward the arena gate, or toward home. Now, granted, if where they want to be, is at the arena gate, I DO work their tail off there, and rest them AWAY from the gate. But I don't allow them to pull me around. I make sure they know how to laterally flex, especially, before I get on (if it's a project horse), so I know I can get them around into a circle, since I focus on circle, serpentine, figure 8, type work, when working their butts off when undersaddle. I also make sure they know an effective one rein stop.
An important peice of 'natural horsemanship' is making the wrong thing hard, and the right thing easy; and it will be different for each horse some times. For some horses, the one exercise may be learned in a couple of 10 minute exercises, and the same exercise may take a different horse several longer more exerting exercises.
"The ideal horseman has the courage of a lion, the patience of a saint, and the hands of a woman..."