Harry Potter and the Advantages of the Plot Hole

This will be a collection of short texts or Drabbles featuring funny ideas, strange concepts and little plot holes of the Potterverse. first: Harry has an idea that will prevent Dumbledore from sending him back to the Dursleys. second: How Dr. Granger and Dr. Granger came to own a toothpaste factory. third: British Airforce to the rescue - a tribute to Alastor Moody.