If you submit a style of music that is not taught at Yale, the best feedback the music department could offer Admissions is: "it's nice, but we don't teach that here." In which case, the supplement has been a waste of everyone's time and might work against you. See: Yale Department of Music > Undergraduate Program > Supplementary Materials
"Music faculty members will review selected audio recordings or scores from advanced musicians, whether or not they wish to major in music as undergraduates. Please consider sending musical materials only if your accomplishments are truly outstanding for a high school musician and if your playing or composing is a strong and important part of your application. Submissions that demonstrate an average or merely competent level of ability for a high school musician will not help your application."
"1. Submissions from instrumentalists and vocalists should consist of two or three pieces of contrasting styles ( e.g. Baroque, Classical, Romantic, Modern, etc.) which demonstrate abilities in the areas of tone, technique, and interpretation. Singers should submit at least one piece in a foreign language. Do not present selections from method books. Whole pieces or movements (as opposed to excerpts) are preferred."
3. Submissions of recordings or scores of popular music or jazz at a high level are welcome.