Why has the grading system left being near impossible for hard tanks like Rek'Sai, Zac, Amumu to get any form of S? The fact that I have 36k mastery points on Zac, 26k on Alistar, and 13k points on Amumu, and I have never gotten anything above an A+. When I get A+'s on champions like those three, I would get an S or S- with all other champions. It makes me feel cheated. I would like if grading could be changed in the future.
Play Zac and Rek'Sai support, that's how I got my S on them.
Getting an S means you're playing substantially better than other people in your role/champ combination at your MMR. Assuming your MMR is stable, that means your play on those champs is probably stable too. So rather than getting some S and some C, you're just getting mostly A and B ranks.
Playing off-role is an actual way to get S ranks. If you decide you want to play Zac mid, that's something that no one else does. So if you play 10 games as him and do terribly, you're contributing to the average "Zac mid sucks". And then you have that one game where you manage to carry, and you'll be much more likely to get an S.
