They have admitted that influence too. Fleetwood Mac's guitar work influenced a lot of people. But by Argus Ash had come into their own, they adopted a lot of English folk influence whereas early Fleetwood Mac stuck to the blues. And Ash's twin guitar work was much more elaborate than any of their prede- and successors'.
Wishbone Ash's work was largely lyrical, they created musical textures with their interwoven guitar work rather than dramatic chorus hooklines - they never had a singles hit, but were strictly an albums band, very seventiesh. By the time they started to try writing singles - late seventies, early eighties - they went on a slippery slope, it was the same time they had second thoughts about Martin Turner's singing which is lyrical/folky as well rather than "grab you by the throat frontman-ish". In fact, in their core sound, his voice is as much an instrument as the guitars and the bass and the swinging drumwork.
Though I do wonder whether the Frampton'ish Goodbye Baby Hello Friend could not have done a lot better with proper airplay. It at least reached German jukeboxes at the time. The intro says a lot why I love Martin Turner as a bass player.
Someone once described them as "the music you might want to listen to if The Grateful Dead are too lame for you and English hard rock sounds too aggressive".
