You're on the right track, but simultaneously doing too much and not enough. One hour is too long for a single session, but a single session (of any length) is not going to fix the problem. Redirection and taking him away from the object of his desire is the correct way to go, but it takes time and a lot of repetition before the message sinks in. Nothing happens in a single day with a 6 month old pup. Except, possibly, the development of bad habits.So we had my dad walk a bit ahead and then stop. I was trying to walk forward and as soon as my dog (Thales) started pulling I'd say his name and walk the other way. I was trying to associate that as soon as he pulled we were going in a different direction. After about 1 hour of this I gave up (I know, probably too long but I kept thinking he was close to catching on. Apparently this wasn't a good technique?). I ended up jogging home while my dad walked hom.