If your understanding of GTD doesn't suit you well, show a teachable attitude and learn, or use something else. When you start throwing out the core principles, you're no longer doing GTD. At that point you're using your own system which shares some similar ideas.
It's like insisting a bicycle should have 3 wheels, because you're unable to ride one with 2 wheels. Just because it doesn't suit you, doesn't mean it doesn't work. Buy a tricycle and ride it happily, but don't criticise the design of bicycles and people who choose to ride them. Some of us are very happy with our bicycles.