Tension and tenses
The familiar old song about Casey and the strawberry blonde has a highly unusual verb tense.
Here's the Transco Chorale version:
Part of the words:
Matt Casey formed a social club
That beat the town for style
And hired for a meeting place a hall
When payday came around each week
They'd grease the floor with wax
And dance with noise and vigour at the ball.
Each Saturday you'd see them
Dressed up in Sunday clothes
Each lad would have his sweetheart by his side.
When Casey led the first grand march
They all would fall in line
Behind the man who was their joy and pride.
Casey would waltz with a strawberry blonde
And the Band played on;
He'd glide cross the floor with the girl he adored
And the Band played on;
But his brain was so loaded it nearly exploded,
The poor girl would shake with alarm.
He'd ne'er leave the girl with the strawberry curls
And the Band played on.
First, brain is clearly a euphemism. The song is about the body part that serves as a young man's brain. If the actual cranial cavity was pressurized, the girl wouldn't notice it while dancing. Alarm is also a euphemism for the source of the girl's quivering.
Second, the constant use of would is rare and possibly unique among songs. It's not a conditional or volitive; it's a past/present imperfective. Waltzing is what Casey habitually did and still does.