Toby has got himself a habit of running off full pelt (or pulling on the lead) to go and play with other dogs. He gives the other owners a bit of a fright with his speed but it means me running after him. Is it possible to knock this trait out of him and if so does anyone have and ideas. At the dog classes they tell me to walk across the other side of the road and distract him which i dont see how that will work long term. He is doing brilliant at everything else. Any help would be appreciated.