I agree - worrying about whether you are, in fact, "layering" in the classical sense is pointless. You carry enough of the right clothing for the season and area you hike in, and don't worry about whether you're properly classifying it. (This goes only for practice; if you're teaching a newcomer to the sport, the descriptive term "layers" is a nice shorthand to help him/her grasp the concept.)

As I'm continuing to move toward my dotage, I'm finding that technical classifications aren't really meaningful. This was brought home to me with a recent pack change. I kept trying to figure out whether my Atmos 50 was an "internal frame" or "external frame"; it has elements of both. Then I realized: it doesn't matter. The pack fits me better than anything I've used, and does everything I need it to do. What I call it is irrelevant.

Caarrying the concept further: does it matter whether the filter I use is "gravity" or "pump"? (The Sawyer Squeeze has elements of both.) Does it matter whether my stove is "gas" or "liquid"? But I'll quit there, for fear of hijacking the thread.