Dungeon musical sequence = GAYDAR OVERLOAD!
A cursory search of the choreographer Eugene Loring shows that he was schooled in ballet and eventually became a dance scholar. This explains the ballet-oriented choreography.
Perhaps it's just that Dr. Seuss's 2-D ideas just don't translate well when projected into real life and become, well, just much more disturbing than they were intended to be.
Keeping that in mind...And I try to keep an open one...The whole dungeon scene just screams "FAAAAABULOUS!" The butt-thrusting dancers with oboes attached to their faces? The bulb horn players shimmy hip-bumping their horns a little too over-enthusiastically? The limp-wristed xylophone players in oversized, fuzzy, pastel mittens?
I either laugh or roll my eyes when the boxers show up and start punching in time to the music. It's like a higher-up told them to "butch up" the number and Eugene Loring tacked on boxing dancers in lavender gloves...And to have one losing boxer picked up and dragged across a giant harp into the gayest, wierdest Busby Berkeley inspired dungeon orchestral finale in film history.
All of that being said, when the the camera pulls back and the orchestra swells at the end of the sequence...It's hard not to be moved by the spectacle.