I really don't care for vocal acrobatics. To come back to Lord Nafaryus, that section is just bad overall vocally. Musically it's really cool actually, but as with so many late DT songs, the vocals seem an afterthought. The guitars were laid down for LN, and then (I guess) James was instructed to just mirror them. He did his best in the studio, but live it's totally falling apart.
And I'm definitely not in the "only recorded media counts" camp. I love Genesis, Peter Gabriel, Queen etc etc. All those artists wrote their music keenly in mind how they would perform it too.