I don't want to comment on what constitutes the general class of "enhancers"; but just to say that the
Oxford Dictionary gives "very" as both an adjective and an adverb.
It is derived from the Latin words "verus", the adjective "true", and "vero", the adverb "truly", and was used that way in Middle English. So you have the 13th century rendering of the christian Nicene Creed calling Christ "very God of very God" -- now translated "true God of true God". With time, "very" became increasingly used to also mean "the exact" or "the actual" thing described; so in
Richard III you have Queen Margaret saying to Queen Elizabeth:
"Thus hath the course of justice whirl'd about,
And left thee but a
very prey to time".
And the translation of Luke 19:40, has Christ saying to his critics: "If these (my followers) were silent, the
very stones would cry out."
Until not so long ago "very" even had a superlative, as in "he would start a fight over the
veriest trifle!"
However, Gilbert and Sullivan, it seems, didn't think "being well acquainted with matters" grammatical was as necessary as math to be "the
very model of a modern major general'.
Intensifier it verily may be, but "very" still works as the simple adjective meaning "true". If your local library has the
Shorter (!) Oxford Dictionary (2 volumes) you'll find the very essence of the history of the word all there
Norm