The basic idea is simple, there is a trade-off between accuracy and performance.This is not really new or that uncommon.
What the fastest way to sort a list of names?
The way I have been doing it for the past 25 years --- build a hash list of the first 3 alphabetical characters and sort this using integer comparison --- way faster than comparing strings.
The results are pretty good --- but obviously not perfect. But good enough so that with thousands of users every day for 25 years, I have never received a single complaint that the sorting is flawed.
