How to get an "S" game with a champion and unlock masteries ? We will find out together !

So, many people try to get masteries lvl 6 or 7 with their favorite champ but they can't find real logic to these "S" grades. Sometimes, getting some 10/0/10 KDA is not enough, and sometimes u can die almost 10 times and still get S- : http://boards.na.leagueoflegends.com/en/c/gameplay-balance/LAgNKAwb-i-still-dont-get-how-s-ranks-are-calculated

So here is a scientific way to find out how grades are attributed to each champion : each time u get a game rating "S", "S-", "A+", or "A", fill in the following short form : http://goo.gl/forms/CAOepfTvBNFcQQ2m2

after a few hundred games, we should be able to know exactly what is taken into account for each champ. I will post results as soon as they make sense.