Koko and the Jingling Chain

For the last couple of weeks I have been riding a friend's horse for him. Koko is a 10- year-old chestnut Arabian gelding. He has a quirk about trailer loading. My friend told me that if Koko refused to get into my trailer, I should take a chain, like the one at the end of a lead rope and jingle it. Then I should act like I put around his nose, but not to really put it on him, and he will get in. Well, it works every time.