I don't think you're missing anything, I think iTunes is grouping them as a compilation, it's just not displaying the compilation in the track order you want.

Two options come to mind - the first is to ctrl/right-click on the column headers and add Track No., then sort the compilation by track number - that gets messy if you have more than one album in the playlist though. The other more permanent solution is to edit the track titles in such a away that they sort alphabetically in the order you want them to play, e.g. by adding track nos. to the track titles.

It's basically a shortcoming if iTunes that you can't define any sort of permanent hierarchical sort order, such as by Artist->Album->Track no. It does something sort of like this instead - if you click on the Album column header, it cycles between Artist, Album by Artist, Album by Year. Album by Artist is the most useful - sorts the tracks by Artist->Artist's Albums->Track Nos., but the artist order is sometimes unexpected...

- padmavyuha
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