Not a bad idea! It sounds pretty similar to k-anonymity [1], which is not a terrible privacy heuristic. But it does have some specific weaknesses. Wikipedia has

Not a bad idea! It sounds pretty similar to k-anonymity [1], which is not a terrible privacy heuristic. But it does have some specific weaknesses. Wikipedia has a good description. > Homogeneity Attack: This attack leverages the case where all the values for a sensitive value within a set of k records are identical. In such cases, even though the data has been k-anonymized, the sensitive value for the set of k records may be exactly predicted. > Background Knowledge Attack: This attack leverages an association between one or more quasi-identifier attributes with the sensitive attribute to reduce the set of possible values for the sensitive attribute. Optimal k-anonymization is also computationally hard [2]. [1] https://en.wikipedia.org/wiki/K-anonymity https://en.wikipedia.org/wiki/K-anonymity [2] https://dl.acm.org/citation.cfm?id=1055591 https://dl.acm.org/citation.cfm?id=1055591