Well I was only saying so for the BLM player statistic; you simply cannot claim how many people play a certain job based on fflogs alone.
FFlogs doesn't show the whole picture, but it is a foundation for certain kinds of information due to the complexity of the data it breaks down. It is a good indication of the more hardcore community since they highly likely make use of fflogs and parsers since it is a staple of being hardcore.
It is also a foundation of information for the midcore raiding community since most raid groups at least one person is likely parsing. It isn't 100% accurate on every count, but it isn't 100% useless either. Casual groups less accurate information since casual groups may or may not upload anything.
In PUG PF groups I notice most of the time someone uploads logs since they appear under my character afterwards. So yeah like I said not 100% accurate, but not 100% useless where all the information it can give should be disregarded.
