A look at the Round indexes and the Traditional Ballad Index shows that early collectors rarely bothered with this song - possibly because the existence of sheet music and the attribution to Whyte-Melville and Coote led them to believe it was pure pop.

Another possibility is that its popularity came after their elderly informants had stopped learning new songs.

Hear Cyril Phillips (1911-1990) sing the "stable jacket" version in 1966:

http://sounds.bl.uk/World-and-traditional-music/Traditional-music-in-England/025M-C0903X0153XX-0300V0

Phillips adds the repeated "lies low" bits that were once commonly songm though the Hopwood sheet music doesn't call for them. Though Phillips's performance is sober, the addition of the "lies low," often sung in falsetto, suggests a drift toward the parodic.

The next step was out-and-out ironic/cynical/bawdy parodies like "The Dying Aviator" and "The Dying Harlot."

Does anyone know versions of these not in the DT?

PS: Poor golfers are frequently called "duffers" in the US, regardless of age.