NT's game is flawless and Shakespearean, they don't need to patch it. The only ones who would change it are modders who wish to soil this myth breaking product with so called "improvements". --- [INSERT SIGNATURE HERE]
So you mean if you stand still for long enough it will eventually drop down to D again? The way it works on PS3 is that if you stop completely it will drop within it's current letter grade, so if you are half way up S and you just stop moving it will drop down to the bottom of S then stop decreasing, it won't go down to A.