another question: my dog plays really rough. He's not dog aggressive at all, just energetic and strong. He's an expert at the neck-grip/wrestle to the ground, but the problem is, he doesn't seem to notice once another dog's cried uncle and doesn't want to play anymore. I spoke to a behaviorist when I got him, and she said not to worry about it--a bigger dog would get the better of him and he would learn his lesson. Guess what? 4 months and 30 pounds later, he's only been bested once (and he didn't seem to notice) and has definitely not learned his lesson. Also, he charges other dogs. He will usually either veer off a the last minute and race on, reign in for a quick sniff, or if it's a small dog, tower over the frightened thing and sniff. It hasn't caused a problem yet, but I think it's only a matter of time before another dog doesn't take well to being charged and starts a fight. Any advice?