So we are simply not talking about the same kind of "partial", thats fine.
While any stat can be farmed the use of this is unknown at best.
All you need is a time component to make farming such a stat irreverent, but even if this wasn't implemented match time by itself will tend to devalue farming because it leads to more mistakes and comebacks and thus lowering your rating by other means.
Farming may even have a negative effect, if for example there are build in thresholds that when exceeded give you a penalty to your rating instead to prevent exactly this kind of behavior.
Farming may even be a mood point, perhaps its a percentile comparative stat along with your damage received as compared to your enemies, so no matter how much you farm unless you find a way to increase that percentile gap between you and them you're not gaining anything out of it.
We don't know if farming stats has any use, maybe yes, maybe no, maybe both at the same time, we simply don't know. We don't even know how to go about testing for this because we simply don't know how many other variables we have to take into account.