It seems like every year at the WGC event at Firestone, and this year is no exception, there is an incredibly wide range of scores, from mid-60s to a lot of high 70s. I always thought this had something to do with the fact that it's usually played right after the British Open and has no cut, and players sometimes don't quite give it their all if they're out of it. But, the wide range of scores occurs on Thursday and Friday too.
What is it about the course that produces these diverse numbers (a wider range of scores than in your average tournament, I submit, especially considering the limited field is supposed to consist of upper echelon players).