Will Your Dog Protect You On Your Walk?

According to this YouTube video, if I am attacked while walking my dog, Bailey would do absolutely nothing to defend me. In fact, she'd likely scurry away with the tail between her legs. 
All this time, I think Bailey is well trained; she is socialized and friendly with dogs and people alike. However, her instincts would kick in if push came to shove, and my dog would protect me. And that's if someone would actually dare to approach me. After all, close to 60 lbs, my Goldendoodle is a reasonably large dog.
It appears I got no clue what Bailey's instincts would communicate to her.