Well, the way we were always taught at my school in CA was certainly effective for me; however, I also practiced an average of six to eight hours a day! I would take a portable cassette recorder to 4-voice class every day and record, then I would practice with that again after class. You should always try to make a habit of getting in a little practice at the lower speed than where you're at. It helps whether you realize it or not! Then go up one speed above your current writing speed. And also try practicing 225 WPM Q and A! If it frustrates you at first, don't give up because soon enough you will notice you are getting more and more of it! Hope that helps.