Well I agree with that, any stats have to have a lot of context included, otherwise, they can be bent to anybodys desire.
I think the problem with debating the F6F and the F4U is that each type had both good and bad qualities, while being reasonably competative with each other. When you get two types that close, just as in the case of the Bf 109 and the Fw 190 series, it comes down to a subjective call. Each arguement can have a counter point, and there is no real way to definitively "prove" one was "better".
Same can be said for the 1940 Spit and Hurricane, they fought the BoB together, and you cant "undo" that. Which was really the "more effective" fighter? its been debated since, and I dare say it will never be "decided", stats alone will prove nothing defintively either...proponents for both will always have a point to counter with, and not unjustly so.
Also, the fact the F6F and F4U fought side by side in many campaigns, and really complemented each other, how do you then seperate that and do a fair comparison? its like baking a cake and then trying to get the original ingrediants back into the packages, its kinda hard to do. You cant "undo" what they did, and then view them as seperate. But, thats the hard part about looking at any one peice of hardware, no matter what, and always will be.