If you're intent is to purely measure their hitting prowess, you shouldn't use WAR as it includes their superlative defensive numbers. They're 5th best in team wRC+ though, so they have still been pretty good with the stick.Going by WAR, the 2013 Giants have the best offense in MLB and the 19th best pitching.
Sounds crazy, but then I noticed that by WAR the 2012 Giants had the 5th best offense and the 18th best pitching (probably because Lincecum was unbelievably bad).
2010 had the 5th best offense and 6th best pitching.
So the "no offense, great pitching" narrative may have been false from the beginning. It is just becoming obvious now, because the pitching is downright terrible, and it isn't limited to one guy they could avoid starting in the playoffs.
And I'm assuming you're using fWAR, which isn't friendly to pitchers like Matt Cain. B-Ref WAR or SIERA would be better things to look at.