When I was younger and a bit down on my luck, I used to borrow my mom's car a few days a week to get to work. She drove it five days a week to work (literally less than a kilometre--ankle troubles), and I had it two or three days. But I drove it from Burnaby to Annacis Island.
So it always made me wonder, would ICBC say she was the primary operator, or me? I put more miles on it, she had control more often. And, ultimately, veto power 'cause if she said no, I had no key
...So I guess she'd be it.