Stu,
Try doing the water therapy fill your tub and if you have to get in with him and hold his belly and let his legs go the way they want to. Just remember my surgeon told me no activity for 8 weeks. So you still haven't hit that 8 week mark yet. And he is already trying to do things. And yes remember he is a senior think of it this way when a senoir person breaks a hip or breaks a bone or has surgery it takes them longer to get better so it may take your little one longer to get better. I know it is hard. Believe me I have been at this for well over a year now. I have found a pure miracle in the wheelchair that he now has from Eddie's wheels. If you think you little guy still can not do it alone after the holidays i would look into a cart for him. He can use it now and all the pressure is off his neck and back. If he gets well enough that he doesn't need it great, but then if he gets lame again it is there for him. That is how I am looking at Babybear's cart now. If he ends up not needing it that would be great, but if he needs it in a few years oh well it was better then seeing him just lay there. Stu your little one is lucky to have you and your family. And I hope he continues to keep getting better.
Just remember after these types of surgeries(very delicate surgery) it takes longer to heal. Not all will jump right up and take off. The younger ones might but then again some might not. He is still healing and it might take a while. Give him a gentle belly rub from Babybear and I.
And you might want to check Babybear's webpage to see how much he has progressed in a short time with the cart.
http://www.dogster.com/dogs/136060