From my own experience. Please, who has a big dog and walks with it a lot every day.
Never wear a leash this way !!!
I was told about this in the first lessons of the obedience school.
Didn't hear ...
Result: Hank suddenly jerked at the second dog. I held the leash, but my finger broke.
Do not want a month of plaster - remember: do not put a loop of leash on the brush!