[tsoof100]

Hi,
I got my Yorkie(Louis) at age 9 months and now he is almost 1 year old.
Ever since he started to lift his leg to pee (marking) walks with him became a nightmare.
He wants to sniff every inch of the street, and he will not continue walking until he had some of this smelling dose, if I won't lift him he will drag behind like an anchor and look me in the eyes like: I will not go any further..

I am using many famous training techniques using a clicker, but even though he is a big food motivated I can't see any progress outside (indoors he is perfect).

To my question:
Had anyone tried some sort of head collar like halti or gentle leader for yorkies?
Is it good for them? I use harness to not damage his trachea and a head collar seems like it could do some damage.
I know there are some sort of harnesses to help training dogs to walk nice, but I would like to know how effective they are.

Thanks in advanced,
Tsoof.