The quality of this advice is suspect.
Speaking for myself, a few years ago I was an interviewee for neurosurgical positions. Now I am the interviewer, so I have a reasonable idea of what we look for. I can tell you that step 2CS is one of many layers to any application. Yes, I would ask you to explain what happened, but it would not be a deal-breaker. The best way to counteract any deficiency is to have an honest, humble, and proactive response ("I had a bad day. I made a mistake on X, Y, or Z. I learned X, Y, or Z, and I will not make that mistake again.").
It is a misconception that only the "best and brightest" apply for competitive residencies. My wife did better than I did on every test, but she went into family medicine. The average applicant for neurosurgery is slightly above average in scores. There are some extreme high and low applicants too, but we look at the applicant as a whole, not only scores.
Another thing you can do to offset your step 2CS issue is be visible (but not annoying) at the residency's educational days. Write papers with the current residents or attendings. Pick one patient to be your "personal patient," (help them recover, assist with their PT/OT, etc). There are many ways to show your value - be creative.
This failed test may prevent you from getting an interview at programs you did not rotate at as a student, but we interview almost any student who rotated with us - no matter what their scores were - if we felt we could work with them as residents.
So I hope this helps. Feel free to send me a private message or email if you have further questions that you would rather not post for fear of a sarcastic/condescending/"skizy" reply.
-greymew
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