If the tags are the same (album artist (auto), artist, album, year) AND they reside in the same parent folder they will be considered one album
I think you also have to sequentially number the tracks (Track No), and set the same the Disk N of M tags too.
I think you guys are mixing two things together here. For MC to display an album as a single entity, it just needs the same: Album, Album Artist (or Album Artist (auto) ). That's it.
As a test, I just changed track #1, disc #1 of The Best Of The Doors to Track 100, Disc 12, Year 1958. It stayed in the same album as displayed. But it changed position.
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Some of the things you guys are talking about with sequentially numbered tracks and the same folder are requirements for MC's algorithm for trying to tell you which albums are *complete*. This does not affect how MC displays tracks in an album though. All it needs are the two above fields to be the same.
For sorting purposes, on a multi-disc set, you absolutely want the track numbers to be correct, and the disc numbers to be correct. Though total discs is not used for sorting as far as I know.
Brian.