Harnesses are so much better than collars to attach the lead in my experience. I used to choke my first yorkie before he got the collapsing trachea issue by pulling so hard against the collar, so you are doing the right thing with the harness! I have the tags on the harnesses, but would never leave them on when they are inside. I just dont think they are as comfortable with the harness on, and if its too loose they can chew it apart if they can get their little jaws under it. If its too tight, it would hurt them, so why leave it on if you don't have too?
