> the total performance improvement is 53%. That's significant.
This percentage is meaningless on its own. It’s 4 ms shaved off a 7 ms process. You would need to time a whole flow (and I believe databases would add a lot to it, especially with network latency) and figure out how significant the performance improvement is actually. And that without considering if the code changes is not conflicting with some architectural change that is being planned.
If you're the size of Shopify that represents a huge saving in server costs and improved customer-facing latency.