I started using Oscar's method about 10 years ago...maybe longer, and I was so impressed with my own results that I started teaching it to others. I have been amazed at how quickly "the Method" has changed people's games.
Weekly I run a 2 hour "Novice +" Clinic attended by anywhere from 8 to 21 players, and since I hate having people standing around in lines, I use a "Game Based" approach where everyone is hitting the whole time. I've found that Oscar's method integrates perfectly with this approach, and my "Novices" have moved into the more advanced sessions and groups quickly...to the point that there are fewer available courts throughout the day. In my mind there is nothing sadder than an empty tennis court.
"Those who the gods wish to destroy they first make angry"