Example: use the standard search box, enter "Louis Clarke". Happily the artist "Louis Clarke" appears in the #1 spot. However the artist "Louis Clark" does not appear until page 5 (result #235), after just about everyone called Clarke, and even quite a lot of people called Clark.
Trying the same thing in reverse, the results are worse. Search for "Louis Clark", and you don't hit "Louis Clarke" until page 23 (result #578). Everyone named Louis gets in first.
This is a time-limited example, because I have submitted an edit to merge these two, as Louis Clarke should not have been created in the first place. But I guess it could be recreated on the test server if you wish.
(Note that the Louis Clarke artist was not marked as a Person, and the sort name was set to "Louis Clarke", not to "Clarke, Louis". Just in case either of these factors make a difference.)
If I do a fuzzy search in Advanced Search mode then I get the results I want. But I guess the editor who created the duplicate artist in the first place did not know to do this.