The point of this new mode is that you don't get just 300/100/50/misses if you hit the note. Instead of that you get from 0 to 300 points, depends on how accurate you are.
For example, let's take a map with OD8. In ordinary play you get 300 if you clicked less than 30 ms earlier/later from the note timepoint, 100 if less than 74 ms and 50 if less than 118 ms. With new gamemode you will get 300 (totally perfect hit) for hiting the note less than 30/(300-100)=0.15ms, 299 points from 0.15 to 0.30 ms and so on. So if you hit -15.62 ms from note's timepoint, you'll get 196 points.
This mode will describe players' accuracy in much better way. Here is the document that illustrates score system for different OD.
For example, let's take a map with OD8. In ordinary play you get 300 if you clicked less than 30 ms earlier/later from the note timepoint, 100 if less than 74 ms and 50 if less than 118 ms. With new gamemode you will get 300 (totally perfect hit) for hiting the note less than 30/(300-100)=0.15ms, 299 points from 0.15 to 0.30 ms and so on. So if you hit -15.62 ms from note's timepoint, you'll get 196 points.
This mode will describe players' accuracy in much better way. Here is the document that illustrates score system for different OD.