I'm not wholly sure I understand what this is about but I'll make a suggestion.

Listen to the Leader recordings of Charlie Wills made when he was into his nineties compared to earlier recordings when he was just a yound stripling of seventy something. By a lot of standards his voice was finally shot. Certainly his breathing was up to five times a line. But I'd still give my right vocal chord to sing like him then. Because he'd never stopped singing in public, he'd adapted his style to suit what was left of his voice, and I don't have the slightest hesitation in saying he was still a great singer.