I wouldn't say the Giants were "lucky" in winning their world series - did we watch the same series?
The Giants were HOT. Pitchers dominant. The real 2010 postseason for the Giants was against the Braves and Phillies. Very hard fought matches. The world series was boring. Texas was gassed. Giants were still riding high.
There's a certain amount of luck involved in anything, especially with baseball. But, in the case of 2010 postseason it was because the Giants were hot and had amazing pitching to silence opponents' offense.
Nuff said.