British Bass David Franklin was 6’7″ tall. He underwent an operation in 1950, and was asked by a physiotherapist if she could test his vital capacity. Lest you think “diaphragmatic” breathing gives you more air, Franklin found otherwise.
Big as I am, and still with two lungs while most of her patients had only one, poor devils, and being moreover a singer with a big development of the diaphragm, she was sure that I should set a new record for the [Brompton] hospital.
In fact, I did nothing of the sort. I came second to a little man who had only one lung to work with…[I realized] I had been drilled in low breathing. I did it with the diaphragm, and the top half of my lungs was unused…
Franklin, David. Basso Cantante: An Autobiography. Duckworth, 1969.