I hang out at several words-related forums online: Wordcraft, Wordsmith, Word Origins, and Wordwizard. Most of the people are united by logophilia, but they tend to clump together into two distinct and oftentimes mutually antagonistic groups: the linguists and the old-school word mavens. The latter are openly hostile to any grammatical terminology or concepts developed later than the late-18th to mid-19th centuries. You know the drill: dictionaries are lax, school children need to have grammar beaten into them (and by grammar they usually mean usage), words must have a single meaning, no neologisms, diagramming sentences should be taught in schools again, etc. I’ve been mulling this over, because recently on one of the forums, a non-native speaker of English asked a question about count nouns. The general consensus seemed to be that the term (and concept) was less than useless. The discussion degenerated further. Of course, sentence diagramming tells us absolutely nothing about why a sentence is ungrammatical.