You actually brought up a good point and you are a perfect example of why people don’t improve in something that is very much based on observational learning. Badminton, like any other sport, is a visual-learning sport. No one is going to read an essay (because I can go on forever in your “detail”) about badminton that is written by a random guy on tumblr. Let’s be honest, if you truly wanted detailed coaching you would have already gone out of your way to find a real life coach instead of asking a guy on tumblr. Don’t judge, always seek and learn for yourself.