You don't have to look far on this forum to find all kinds of people using decidedly non-GTD techniques in customized, hybrid approaches, many inspired by a variety of traditional practices and other, more formalized programs. I don't know what people call them, but it's not David Allen's GTD.
In my experience, such home-grown systems seem more common than true, by-the-book GTD. In fact, around here, GTD purists are frequently branded as zealots.
In my experience, such home-grown systems seem more common than true, by-the-book GTD. In fact, around here, GTD purists are frequently branded as zealots.