Thanks again for all your helpful advice - so far he's not responding well to the long lead, but we'll persevere!
On another note I completely disagree with this statement and find it offensive. My dog is not out of control or obnoxious. He doesn't jump up, or bark, or anything else that could be construed as aggressive. He just places a stick or a ball at people's feet and usually lies down next to it, wagging his tail, albeit making rather intense eye contact. If anyone chose to kick a dog while it's lying on the ground, it is absolutely an undeserved attack, and I would call the police immediately. Please be kinder with your words when talking about other people's dogs, and ensure your comments are based on the information provided rather than assumptions you have made and have some respect.