The blog post by Piyush Singh discusses optimizing application performance for SQL databases through the use of the "duplicate indexes" topology pattern in CockroachDB. The focus is on improving read performance, especially in scenarios where data such as zip codes or user authentication details require frequent access and read speed is prioritized over write speed. By creating secondary indexes in multiple geographic regions, this pattern ensures that reads are handled by local data centers, minimizing latency and enhancing user experience, even if users migrate between regions. The trade-off is a decrease in write performance due to increased data replication, though the write latency remains within an acceptable range. This approach ultimately leads to near-instantaneous read experiences, making it ideal for applications where fast data retrieval is crucial.