Re: [ANN] Bancor Protocol - A Hierarchical Monetary System & Decentralized Exchange
I do not see what problem the Bancor project is attempting to solve. The double coincidence of wants was solved by money (fiat), and bitcoin is an extension of that. The white paper is not properly written.
I think that what you are referring to is the double coincidence in bartering goods, but from what i understand in the white paper they mean that Bancor solves the double coincidence when swapping money, as in you have dollars and want euro but to do that you would generally need someone on the other side willing to trade his euro for your dollar. i could be wrong tough! 
That's accurate! In a sense, Bancor solves the DCoW problem for tokens, by enabling them to use other tokens.
Tokens hold other tokens in their reserve (using their smart-contract) and provide a conversion service between the token and its reserve/s, using the calculated rate as detailed in the whitepaper: https://goo.gl/1WNx2l