When I listened to The Beatles yester-day, I noticed a few small things about the vocal articulation in "Sexy Sadie."
Although it's a singular form, the melisma'd "ev'ryone" in the repeated line "You made a fool of ev'ryone" musically gives a sense of the span of "ev'ry." (For the record, I think the notes are D B D E D B the first time and E D A G A F# the second.) Near the end, it's articulated something like: E D D' B A G F# E D. Here, it spans an octave, which also musically gives a sense of the span of "ev'ry."
The other thing I noticed is that "rules" in the first "You broke the rules" in the second verse is sung in such a way to represent that brokenness musically. I think it's a melisma (E to D) combined with vibrato. Whatever the technique, the word is sung in a broken manner to illustrate the lyric.
While picking out specific notes in order to write this post, I also noticed something interesting about the "Sexy Sadie"s that start each verse. They're sung to the phrase A B G E, which - when the A is doubled (A A B G E) - is the same musical phrase to which "Eleanor Rigby" is sung at the beginning of the first and third verses in "Eleanor Rigby" (although the rhythms might be a bit different). In both songs, the titular character's name is sung at the beginning of the verse and to almost the same musical phrase.
