If you want more information do a Google search on Oscar Wegner or "play like the pro's with Oscar Wegner"
or search YouTube for the videos from Oscar Wegner.
His method was used in Spain, Germany, South America and all the former Soviet Union countries, They all adopted his method, Look what happened to their Tennis players and then compare it with the UK, and USA!
(The only American players that adopted Oscar's method was the Williams sisters!)
I hope you like it!