Good article, though I don't agree with it all.

It is harder to grow software than it is to initially build it. Preconceptions bite you on the ass, data structures don't allow for new features, side effects multiply.

You don't need to learn the layers. In fact, if you're learning all the layers, you're probably an innefective coder. This is not to say that you shouldn't investigate the layers or have a poke around the layers. But, software's about reuse and reuse is about reusing other people's work via known interfaces without worrying overmuch about what goes on underneath the hood.

I'm actually more of a debugger than a profiler, and as much as I'd like to believe that my way is as valid as his, I suspect that he's probably right on this and I'm probably wrong.