"I think I'm seriously losing the plot here. Why was Henry Cowell discussing MacColl and Lloyd on a record of music by Willie Clancy and Michael Gorman?"
He wasn't
Reg Based his statement on the last sentence of this sleeve note. Neither MacColl not Lloyd are mentioned in the insert:
BIOGRAPHICAL NOTES
Michael Gorman is a 58 year old traditional fiddler from Co. Sligo, Southern Ireland.    He has "been playing fiddle since he was 8 years old.    James Gannon .of Achontry, Co..Sligo, a great fiddler, heard Michael whistling fiddle tunes and offered to teach him the fiddle if he could get hold of an instrument.    Michael got his fiddle and was apprenticed to Gannon and later to Michael Gorman, who taught every fiddler of note in West of Ireland.    Gorman soon became a notable fiddler in the county Sligo style, a style which (unlike that of Donegall) eschews heavy down-bowing and achieves its effects by highly elaborate fingering.    From being champion fiddler of the district, Michael became regional champion and later national champ.    He has represented Ireland at International folk festivals. In his younger days he was also renowned as a dancer with a nice, clean style of footwork.    Even today, after a lifetime of heavy work, he will, if moved or excited, dance a jig or a hornpipe while accompanying himself on the fiddle.    He has made many recordings for B.B.C. folk music archives, has broadcast and been in television.    During the day he works as a railway porter at Liverpool Street Station, London, and is one of the folk musicians who is helping to build the British Folk Song and.Dance Ensemble.
Jim Carroll