Sigh, indeed.

Yes, Nerd - for the sake of clarity I'm using Green Man to mean Foliate Head, though that clarity obviously does not extend so far as to the vague notions of the Green Man as pageant figure, which have little (or nothing) to do with the extant folkloric figures Lady Raglan was thinking of when she named the foliate heads Green Men.   

As you've indicated, the link is indeed very fine - so fine as to be barely perceptible, being based on a notion that links the Green Man to the wild-man carvings, which in any case would appear to serve a definite didactic purpose other than depicting carnival figures (see my previous post for an account of the wild-man figure at Whalley which is depicted in terms of animal lust) and those few (two?) Foliate Head carvings where shields / clubs are present, which are historically and stylistically miles apart.