i would have to say I disagree with this. By returning him to the herd every time he gets nervous/stubborn, you'd be giving him what he wants and just rewarding his behaviour. Not that im saying you should just drag him away kicking and screaming, lol, but work in small steps.
Like others have said, I think groundwork will help. My gelding does the same thing occasionally, he will stop and refuse to go further, he can be nervy and isn't very confident, but when he does I just consistently ask him to go forward, squeezing and clucking. After a while he\ll get sick of it and move, as soon as he does, even if it is just a step, stop asking and give him a rub and praise him, then as Sonny said return him to the herd, therefore rewarding his obedience.
Each time you go out increase the distance until he is happy to go away from the property. Works with my boy, just requires alot of patience, lol, we once spent more than 1/2 an hour to get him to walk up to a piece of ribbon stuck on a log, haha, he's such a baby. We started off meters away, and each time we'd just get a step closer, and after a few steps i'd take him away for a few minutes to give him a break then come back. But by the end he would walk right up and sniff it and would walk past it back and forth without an issue.
Sorry for the loooong post, lol. Hope it helps!
Remember this is not a dominance issue...it's a nervous issue.
Okay, let's say your horse is DEATHLY afraid of tarps (my horse was). Each time he passes a tarp he makes a HUGE circle around it. You are told to make your horse walk over the tarp. How would you make him walk over it? Would you FORCE your horse to get over his fear? Forcing him to ignore his intuition saying that the tarp is a predator?
He is truely afraid of the tarp, so forcing him just to get over it not only won't solve the problem, but the horse will loose trust in you because you are not being considerate.
Instead, you *should* let hte horse approach and then when he starts getting nervous, turn him right around. Then approach again, and he'll soon go farther and farther and farther until, what do you nkow...he is on the tarp. SOon he'll walk, trot, and canter over the tarp like it's nothing.
The horse is look looking at you as the herd leader instead you are just "the person on his back". Groundwork will help, but forcing the horse to go past his confort zone will not solve anything...just prove to the horse it's horrible to go away from the herd