Why is Gwen able to play music she has never seen before?

Gwen is able to play music she has never seen before due to her strong sight-reading skills and extensive musical training. She has developed the ability to quickly interpret musical notation, allowing her to understand rhythms, melodies, and harmonies on the spot. Additionally, her familiarity with various musical styles and genres enables her to adapt and perform new pieces confidently. This combination of skill and experience makes her an adept musician in unfamiliar territory.