"communicate" seems like the really interesting part of this, but gets a one-off mention only.
like, how does this communication work? how does one sleeping person communicate skills to another sleeping person?
have we found the mechanism? was it awake poeple communicating to sleeping people? the reverse?
Stephen LaBerge's book explains, in detail, how they would communicate with lucid dreamers during their research. I don't remember how the researchers signaled the subjects, but if I remember correctly, the subjects would communicate with researchers primarily through eye movements. I can't say if the methods are related at all, but the book is worth a read.
My thought too. The title appears to assume there's nothing special about the 'communicating' but there is about the 'practicing'. Should it not be 'New research suggests people can practice skills and even communicate while dreaming'. I would like to know more.