My boy who is 19months old started to cock his leg at 9month. I know that with my boy, my brother wouldn't walk him because he was embarrased.
I know that I liked it when my boy squated, very easy toilet training when he was a puppy especially on cold nights all in one spot rather than all around the back yard.
All I can say he will do it when he's ready and he may not ever cock his legs ever!
Nat