I'm studying right now for the upcoming ACT and I currently have a 35 English and a 35 Math on the ACT. Think of it through the eyes of your competition, do you think they would like you to retake it and potentially get a higher score? Probably not, because that might cause you to get in instead of them. If I get rejected I don't want to have to think "Well maybe if I had spent 4 hours of my life bubbling in circles, I would have gotten in." If I get rejected I want to be able to say that I did everything that I possibly could have done and that I tried my best but came up short.