Well in terms of Calzaghe, u cant really say he ducked anybody. Joe and Enzo Calzaghe always wanted the biggest fights they could get, not only for the sake of boxing but also because of the fact they like to make big money. Joe did fight the best opposition he could locate.
The only flaw in his fights i can really think of is him failing to rematch Reid, but then agin others dealt with him didnt they.