And sometimes that’s followed up with “…not a communication method.”
Well, first off, I’m a native cuer. I can cue anything to another cuer, and he’ll understand everything I say, and vice versa. It doesn’t matter if we voice or not; all the phonetic components of English are right there on our lips and hands. That is communication! It’s complete language access.
If you want to get picky about it, everything is a tool– i.e., a way to accomplish a particular end. Even sign language is a tool. Spoken language is a tool. Written language is a tool. They’re all ways of communicating. Cued Speech is an exact representation of an existing language.
The nice thing about Cued Speech is that it can be used by itself, voiced or unvoiced, alongside sign language, as a speech therapy support, as reading/vocabulary support, with d/hh kids, with autistic or learning-disabled kids, with ESL speakers…
The key word there is “can.” Its use is ultimately up to whoever uses it. Really, the fact that Cued Speech is a tool is probably its greatest strength: it can fit into a variety of approaches without detracting from their central philosophies.