I think “chancing” had a bad rep because of the forum by that name on this site, where it looks like it’s mostly high school students trying to psych each other up (or psych each other out) by flinging out improbably precise estimates of admission chances to other high school students. No one – perhaps not even an actual admissions counselor – can pinpoint that a valedictorian with 3 activities and 5000 volunteer hours a year in Honduras has an 85% chance of being admitted while a similar student with 4750 volunteer hours in Senegal only has an 83% chance of being admitted. They might be able to give you a rough estimate based on research and experience which factors are weighted more heavily or which factors
I do think that high school students could benefit from more realistic and carefully thought-out advice using the principles that Much2Learn describes though. There just needs to be more caution and conscientiousness that I don’t really see from most of the “chance” assessments, where you get folks assuring minority kids that they’re basically assured a full ride at Harvard because they have a 4.0 GPA and other folks telling kids that their sub 2100 SAT score means that they shouldn’t apply to any selective schools.