Shyvanna's End Game Ranked Bugged?

I just noticed playing Shyvana, that it doesn't seem to rank people properly. A few games of mine, and reports from other people on my friends list say that their scores feel off at the end of the game since Patch 6.23 Shyvana rework. It seems to put people in the A rank no matter what the results are. One person got an A- for a 0/11/3 score and 66 cs at 25 min. Another person got 25/1/6 172 cs 5 drags, 1 baron, and rift, in a 40 minute game, and got an A. Does anyone else notice a trend like this? Feel free to comment.