"I might be quibbling here, but only one of the artists appearing on the disc (Eliza Carthy) is actually a subject of the My Music series"

I quibble your quibble - it's two. Eliza Carthy & Athena. I don't think Proper distribute the other three artists in the series. I just got this CD in Virgin, sorry Zavvi (or Chavvi as its known round here) for £2 and see that several of the tracks are "exclusives" too. Not a bad deal to keep in the car glove compartment, and it would be churlish to complain about very amateurish design.