Elton John, "Sorry Seems to be the Hardest Word"

Repeating a fast sequence of notes using a single finger in the Right Hand is perhaps "Sorry Seems to be the Hardest Word" greatest technical challenge. The way to achieve it is by using larger muscle groups located in the palm of the hand  and using the whole hand instead of the finger alone in order to achieve the desired speed. Classical guitar players ought to be very aware of the workings of their musculature and see playing as the result of a well educated playing apparatus and not as the result of playing with thoroughly trained fingers. Abel Carlevaro was the first  guitar teacher to put it in writing in his treaty on classical guitar technique "School of guitar". I invite you to read the Carlevaro Technique pages in the Technique section of mangore.com where I explain in depth and very exhaustively Carlevaro technique.