I agree that the QBR has flaws. Which I mentioned here:
I think true football enthusiasts watch the games and make their assessment from them. But short of watching every game savvy fans can look at the
many stats to create a picture and not just rely on one stat which you do a good job of listing in your post. But all stats have flaws and as we should try to understanding the inherent limitations of each.
I don't think any stat should be assasinated because its being used to 'prove' something we disgaree with. If I used QB rating to say that QB X is better then QB Y it doesn't mean the QB rating itself is worthless.
Any how here is a much smarter article and comparison:
Luck vs. Griffin, a Statistical Comparison
http://fifthdown.blogs.nytimes.com/2...al-comparison/
My thought was and remains that clearly there are tweaks that need to be made to how it accounts for running impact:
But, it should be noted that the QBR does rank Griffin ahead of Luck in terms of passing: