Well, not ALL HS drivers suck, but a large percentage of them do. I know I was a terrible driver for about the first year or so of having my license. Until I got some experience (uh, don't do THAT again was a common lesson to myself). Fortunately for me, I didn't wreck the VW Dasher before I removed my head from my buttocks.
I drive fast on the highway, sometimes aggressively. I drive pretty reasonably on surface streets. But no matter where I am driving, I am keeping an eye on the people around me and trying to determine what they are going to do next. Because you never know when you are going to run into (blue hair, dumb ricer, boy racer in dad's BMW, inexperienced HS driver, plain old moron).