Pretty much useless topic but if I had to choose I'd rather go with good coach. Good coach can always make a bad team a good one while bad coach will just make a good team play at the same level. At the very best...
Trentino dominates the world for 3 years in a row without players from Brazil, Russian or American NT /except for Visotto who became national player because of his performance in Trentino/ first with one, and later with two players, best on their positions Kaziiyski and Juantorena. Brazil NT for example had at least three "best in the world" on that position: Dante, Sergio and Ricardo Garcia. A lot of people think Giba and Gustavo Endres best in the world on their positions too. How does bad coach can achieve such success in such conditions?
http://en.wikipedia.org/wiki/List_of_fallacies