I find Phil Tanner's singing moving because of it's contained exhumerance - a recreation of the situation each time
There's a magnificent photograh of him singing to a group of old people, many of whom apear not to be listening
Rather than attempting to win them over, he appears to be singing for himself - for me, the sign of great singing

I always like to imagine he was singing 'Henry Martin' when that Picture Post photo was taken in the old people's home - you're right, he certainly is generating his own excitement there. 'The Parson and the Clerk', on the other hand, is a well-crafted piece of comic singing.