Maybe it will help if you first understand what friction is. Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.
Ref - http://en.wikipedia.org/wiki/Friction
Do you really think the string is sliding around the diablo?
Everyone has the right to be stupid... it's just that some people abuse the privilege...
Balance - 31.0 cm, Weight - 358 g, SW - 346 Kgcm^2