Whilst it is useful to compile test results and keep them to yourself it is equally more important to the peer group to circulate such information at a point in time and space. This is important relevant to the analogies often quoted in life about (a) living on one's laurels and (b) the grass growing under one's feet.
Some good examples where sharing information is far better than keeping it yourself.
1. In a court of law the chance to present alternatives is lost in a one-chance-presentation if prior disclosure has not been made.
2. The chance to form common ground with one's peer's is yet another example
3. As a third example, what about actually knowing what type of information is available. Do remember some love the idea of psychological smoke and mirrors. However, forensics, the law of evidence, universities and education are poor for it for those the system that indulges "bluff". Also, bluff has no place in forensics and evidential standards.