What does "better" mean anyway?

I think I should preface this post by saying in advance that I apologize if any of this appears rambling and whiny, but some of the issues in the articles really intrigued me. As with last week, I shall reserve the majority of my comments for class, but I just couldn't wait to bring up the issue of YA novels making students "better" readers. In particular, I am speaking of the "Research on Young Adult Literature" section found on page 99 of our deliciously cumbersome course pack. I guess my concerns primarily stem from the second point on the page (the more young people read, the more practice they get, and the better readers they become). To me, that seems terribly vague. By what standards are we concluding that these students are "better readers"? Do we mean simply that they read faster, and consequently read longer books in shorter amounts of time? Is retention a component to this "bettering" of children's reading? Ideally, not only would students gain speed and retention but also the skills to synthesize content with cultural circumstances that not only relate to them but also have impacts on their lives. But is this level of reading improvement really what the article is talking about? Correct me if I'm wrong, but I don't recall a qualification of the term "better". The articles consistently state that students enjoy reading more if they get to pick their own books. But since when did our enjoyment become equitable to purposeful actions? I don't understand the inherent value of doing something as opposed to something else merely because students enjoy it more. When pressed, I think many students would say they enjoy YA novels more than canonical (boring) texts, but they enjoy reading magazines more than reading YA novels. In fact one of the articles mentioned that something like 80% of students said they're favorite reading material is magazines. Better yet, most students enjoy watching TV or reading blogs even more than magazines. Why not teach those things?
I reject the pervasive assumptions of classic literature that suggest that such texts are "mostly written for well-educated adult audiences" and "does not fully meet the needs, interests, and abilities of most young adults." What, exactly are these needs and abilities and how are YA novels a viable substitute for other works. I also have problems with the ideas presented on the bottom of page 99 that claim that "young readers' success with any work of literature is determined by how closely their interpretations match the 'authorized' interpretation" thus rendering students' responses to literature "limited to naming the 'right' answers to teachers' questions." Can it not clearly be seen here that the problem lies not with the text themselves but the manner by which the text is presented to the reader? I say screw the authorization, research, and tables and teach the kids what they need to know from a text with which they more than likely have an averse relationship. What's so wrong with playing Dead Poet's Society every now and then? As the research indicates, it is "far more likely that young people will become lifelong readers if they are given positive experiences in reading." Again, however, we are left with the problem of the inherent value of reading in and of itself without proper instruction as well as the research's operational definition of "positive" experiences. To be clear, I have absolutely no problem with YA novels. None whatsoever. But I think there is much more academic value to reading a children's classic about a racist boy's transformation with a runaway slave compared to teaching the timeless struggle with making varsity or being stuck in the hellish confines JV football...high school can be a real drag!