Message Man is Beatle Man with a new set of lyrics by Scott.
But at the same time, according to Scott in an interview for Mark Dillon's new book, it was the up temp tune that Brian and Scott then transformed into MAD.
On another point, the lost demo talk is also nonsense because that track -- the demo of MAD -- was officially released on Brian's website.
... and also on a sampler given away promoting an Australian music festival. Details on 10452.