What we found was that the kids at my son's school who were in the high SAT cohort all eventually told eachother their scores. This did not happen until senior year. At that point they kind of rooted for eachother, and kind of competed. It was quite friendly - the school is Catholic and known for a "whole child" approach that discourages wild stressing over academic performance. But the kids did figure it out themselves.
In our case, the GC certainly found out his scores. It was a good thing. Then S told the teachers, senior year, where he had a relationship and they were cheering him on anyway. The ones who wrote his recommendations were obviously in this group.
There seems to be an organic path for the communication of these scores, to those who will hear them well, at the appropriate time.
There are many things to worry about so I wouldn't pick this one
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