I (and likely the respondent) was using Slavs instead of Slovenes. Most everyone in that part of the world is A Slav. Croats and Serbs included.
As a 3rd generation descendent of immigrant Serbs, I'm familiar enough with the tribal nature of that part of the world to know that even though the people in that region are far more similar than different, they still are able to find reasons to kill each other over minor differences, both real and perceived. From time to time they get along, but it's always an uneasy truce as opposed to a lasting peace. Of course, once many of them got over here, they were treated as a uniform group, and poorly (like every other immigrant group), so learned to appreciate some of the similarities more.
This this thread is off the tracks