I have complex feelings about the Times article, but the type of feedback he is asking for isn't easy to get unless you have a mentor on your side or something with some serious one-on-one time, like a senior thesis. Ultimately, if your child wants to receive real writing instruction, encourage him to be persistent.
I agree wholeheartedly with apm221. It's much more likely that a student will get good feedback if he specifically requests it. Most of my students don't respond to feedback. I doubt many even read it.
If your child wants to experiment or attempt to be more sophisticated than expected, my advice is to encourage the child to talk to the teacher about what he or she is trying to do. Personally, I encourage taking risks (even if students aren't able to fully reach their goals). However, I need to know what the student is attempting in order to assess the work. It's not always evident. You get that information in a writer's workshop, not so much in other types of classes.
The reality is that teachers at the high school level have to use rubrics these days because they need to teach kids to write essays that fit into the standardized testing box--the kids can't be successful on writing tests if they don't play the game.
I used to score the writing portion of the GRE, and that was a mess. What was most important was that you and another scorer gave the same essay the same score--or at least an adjacent score. As a result, the scorer focused on guessing what the other reader would rate the paper instead of being focused on the paper itself. Today ETS uses a human reader and an E-rater. I don't have experience with that, but the problem would seem to me to be the same: as the human, you're pushed towards calibrating yourself with another entity--the essay is the thing between you. Does this lead to weak, formulaic writing? Yes, but that's what I see happening.
When it comes to "Write the way the teacher wants is how you get by," I'd say that a positive way to phrase it (if it is helpful) is know your audience. I know that's lame, but if it helps you get through the day...
