I'm not so sure I hold with MacColl's pronouncement of
"They sound very nice but they wouldn't get a rowing boat across a park lake" as applies to any working singers.

His expertise was, after all, not inclusive of either rowing boats
or park lakes. He was a musician and actor.

As a counter-example, I offer up the Menhaden Chanteymen; both the
field recordings and their later performances suggest that they were
indeed fine singers who made a fine sound...while at work.

I would expect that in any places where chance brought talented
voices together to sing while at work, the things occurred which
most often occur when good singers get together.