I haven't read Shannon's paper, so I'll have to take your word that RAW is misinterpreting. Does that make his mention of noise in systems (casually applied though it may be) invalid?

No, RAW's further discussion of noisy communications channels is pretty good.

(Shannon's paper proves interesting and surprising things about noisy communications channels, but it takes the noisiness as given -- contra RAW, it does not prove that all communications channels are noisy.)