Riding with my spouse many years ago she had a little dog carrier on her front bars for our longhair miniature dachshund. The dog loved to ride, would hang its head out the front in the wind, but would go nuts if someone passed us. The dog would be OK if you road up along side, but as soon as you got so much as a wheel in front the dog would go nuts and start barking, yipping and jumping around inside the carrier, and stay that way until lead bike was about a half a block distant.
That says it all.