Formal structure of  "I Me Mine":
Intro (v) 0:00-0:06 186 bpm
Verse 1 0:06-0:39 186 bpm
Middle 8 0:39-0:57 124 bpm
Verse 2 0:57-1:29 186 bpm
Middle 8 1:29-1:47 124 bpm
Verse 3 1:47-2:26 186 bpm
Comments: "I Me Mine" is very much the product of Phil Spector's producing. Originally the tune was significantly shorter, concluding after the second verse. Spector edited the song, essentially copy/pasting the middle 8 and verse 2 from 0:39-1:29 to create the middle 8 and verse 3 (which is why the two middle 8s and verses 2 and 3 are 100% completely identical). Structurally speaking, what Spector's addition does is extend the song from a ternary A-B-A' structure into a 5-part rondo: A-B-A'-B-A'. And "I Me Mine" is just the second Beatles song to employ a rondo structure (which is more associated with classical styles than popular styles), behind  "I'll Be Back".
Helping articulate the formal divisions is a metric modulation. The verses are all in a quick simple meter (around 186 bpm), but to transition to the middle 8s the subdivisions remain the same (372 per minute) while the macro-beat shifts to a compound meter that is 33% slower (around 124 bpm).
This blog is a workshop for developing my analyses of The Beatles' music.