Yep, lots of real world workloads shard very well. That wasn't my point. My point was that "most" distributed SQL Databases that do sharding will do very well on TPC-C. You can google search for equivalently impressive results for many distributed SQL databases. Each of them can keep adding more warehouses to the TPC-C workload along with more hosts and shards to the distributed SQL database to push the TPC-C TpmC results into the millions.
