Cathedrals Stacking Vocals on “There is a Fountain”?

Yesterday, I was listening to one of my favorite Cathedrals projects, You Ain’t Heard Nothing Yet. It was released in 1979 and was either the final or one of the final projects recorded with Roy Tremble and George Amon Webster.

The Cathedrals sang the first verse of “There is a Fountain” acapella to start the project, and another verse acapella to close it. George Younce sings the melody, and the rest of the parts are inverted above him. What I didn’t notice until yesterday is that while George Younce’s voice is unmistakably on lead, it sure sounds like there is a bass harmony part beneath it. That sounds like Younce’s voice, too. (Plus, the song is keyed in G, and the bass part goes down to a D–few baritones could hit that note the way it was hit here.)

The thought occurred to me that Younce may have done the two leadoff notes for each line before handing off the melody line to someone else and slipping back down to a harmony part. But especially on the choruses, where the bass part is also audible, it’s unmistakably his voice on the lead.

Does anyone know if he overdubbed his voice onto a second part for these tracks?