Found a little more detail. From the New York Times, Oct 26 1975 (https://www.nytimes.com/1975/10/26/archives/bob-coltman-opens-folk-music-series.html)

In his own original songs, however, Mr. Coltman used a softer, easier vocal style, applied to a wide range of subject matter—from a touching ballad on the death of Robin Hood to a lively, foot-pounding jig about country fiddling, “The Pony Tail Bow.” And, as an advocate of homemade music, he deplored its passing with “I Can't Play Nothin' But the Radio.”

Still nothing substantive but at least we're getting somewhere