A yes no question.

My latest observation about Buffy's language quirks.

When indicating no or a negative without a word it's very common for most speakers to use the phonetic head-shake: "uh-uh" ['ʔʌʔʌ].

I'm not sure I've ever heard Buffy use that exact sequence. It's close tho. The metric foot she uses is identical: a trochee. But Buffy eases into the sound with a nice soft glottal fricative [h]. I guess it would be ['hʌʔʌ]. This reminds me of the kid in my high school choir who I mentioned a long time ago because he sang his solo line "ever more and ever more" as "ever more hand ever more." He always cut the note short after the first "more." In normal speech after such a pause the following vowel would likely have a glottal stop onset. But that can sound awful when singing. So he tried to ease into the vowel.

I've been assuming that Buffy must have a similar aversion to the abrupt onset of a glottal stop. But if you've ever heard her speak you know that abrupt starts and forceful interruptions are not a problem for her. Her reactions seldom hold back or ease into their intensity.

So why the "huh-uh" instead of "uh-uh"? I have a new theory.

Before she took her lofty perch amongst the renaissance scholars Buffy was a mathematician. She believes in inverses and reciprocals as types of opposites and complements and so has a chiastic view of opposed expressions. What is the affirmative phonetic head nod? It's "uh-huh" [ʔʌ'hʌ]. Note that the affirmative is an iamb. The negative is a trochee. Most speakers invert the tonal contour and change the onset of the second syllable but Buffy did enough algebra to know that you can't just split up an expression haphazardly. So she brought the entire syllable along with the tonal shift. Buffy's negative is a more complete inverse of the affirmative.

Yes: [ʔʌ 'hʌ]
No: ['hʌ ʔʌ]

This could be the new productive thesis/antithesis construction.