Yes, now that you say that it is better with a leash, you are more in control, at the same time, I didn't need it much for the girls, they are very good about getting their business done and coming inside. With Zander, its a whole different thing... he gets distracted, squirrel, and forgets why he is outside. I am working with him to go outside without a leash and do his business, it works if there are no distractions.
The other thing is.. instead of a clicker have you tried, snapping your fingers? mine understand the snapping. See, I thought if I don't have that clicker on me than what good is it? my fingers are always there ;D so I use that instead. Just sharing.