"If you have any creativity within you as a musician, then experimentation will happen."

This is a euphemism for "forgetting the real notes/words and just faking it".

Not necessarily so. It's usually about knowing your material and genres of music thoroughly - so thoroughly that the urge to extend the boundaries of it becomes very strong. You rarely get creative and fluid improvisations from jazz musicians (for example) who don't have a thorough knowledge of the harmonic and melodic structure of the tunes they play.

There seems to be some contempt for the word "creativity" on the part of some posters here. How sad, if so.