Isn't it ironic that Sound of Silence (the Sy & Garf song) is such a minefield ?

The other day some guy requested it, we sort of faked it but I decided to really get it right for next time.

The way I analyze it, bars are usually 4 beats, but there are some 2-beat bars. Ok, happens all the time, but ....

There are 5 verses.

Verses 1 and 2 have the same structure with two 2-beat bars at the same places.

Verse 3 has only one 2-beat bar.

Verse 4 has only one 2-beat bar but it's the other way around.
Also the phrase "and echoed" is placed differently compared to the other verses.

Verse 5 has no 2-beat bars at all.

(I can post my complete transcription if anyone's interested).

Did they really write it that way? Are they just following one another? How can they make that work at all ? Do they always perform it the same way ?