And even if Marco Polo went to China, did he come to Yunnan? That is of course the question that would interest us here. Well, all the points Wood makes apply even more to Marco Polo's trip down to the very fringes of the Chinese empire and beyond. As remote and unexplored Yunnan was at his time, Marco Polo's account of Dragon, People with Golden Teeth and the salt mines, together with implausible dates and travel times seems much more a second- or third-hand account written up far-away rather then first-hand experience. Even if Marco Polo went to China, he did not come to Yunnan.
Secker and Warburg
1995, ISBN 0813389992