I constantly battled people about the choke collar. But, here's what happens. If someone put one on you, you'd learn REAL quick. It's not a lifetime thing. It's a few weeks thing if you're consistant.
You need to talk to them during that time. You give a yank, then a command. If he complies, he gets some sort of treat...a hug, a doggie treat, whatever. If he doesn't, you redirect and ignore. Just go the opposite direction.
Good luck with this.
Abbey