This analysis is flawed in that it assumes that the host with the closest geographical proximity should always provide the lowest network latency.

Very often it does, but especially for smaller countries that do not have the same number of peering points that exist in the US or Europe, latency will appear out of whack when compared to geographical proximity.

For this test to be valid, you would need to measure the latency to the remote host from all four servers to determine if indeed the ideal route was chosen. Even then the latency may vary depending on the time of day or other network conditions.

From a practical standpoint, a simpler and more accurate metric would be to compare page load times in different geographies before and after enabling Route 53.