I need to write a report on a concert that I went to for my music class. I saw Margarita Escarpa performing at my school and I'm having trouble finding ways to describe how she was playing.

Particularly, she did this one thing (first off, know that she is a classical guitar player and finger-picks) where she would pick constantly fast on the high e string, but with her thumb she would play the lower strings slower, so the song sounded like it was both fast and slow in tempo at the same time. The fast picking sounded more like it was accenting and the slower picking was the actual song being played if that makes sense. How could I describe that in better words. This is for a music class report after all.

Oh ya its due Monday so any quick help is appreciated :D

Here is a link to some youtube stuff from her:
http://www.youtube.com/results?search_type=&search_query=Margarita+Escarpa&aq=f