What seemed really strange to me when I watched this is that she seems to be shoving herself off the bike (you can see her pushing on the guy's back), rather than holding on. She doesn't even make an attempt to grab his shirt.
WTF!! Was she BLONDE, by any chance?!
Perhaps she thought the reoad was nice and smooth, and she could just coast to a stop.
But that was a grade A crappy thing for him to do...there are a few girls I have done little wheelies with, but they always knew it was coming and were experienced with that sort of thing.
And it was never at high speeds or in traffic.