I've been around here for some time and I know that some Mp3tag users keep information about the overall number of tracks of a given album
My question is: why?
If you want to use this piece of information for distinguishing the same album in more than one edition, because for example the same album can have 18 tracks in USA and 20 in Europe then that is not enough- the album can multiple re-editions on both sides of the Atlantic Ocean. [For that one should use the distinguished serial / pressing number, or whatever it is called, that identifies precisely what disc from what album or at least what album it is]
So what is the point of keeping info about overall number of tracks?
And the second issue: what if there is a hidden track? Do you recount the tracks accordingly to the reality and not the official tracklist?
I can tell you why I keep this information (I can't speak for others):
For me it is important to ensure that an album contains ALL tracks. So if I see that an album has 18 tracks (because the "overall number of tracks" says 18), I can check that my folder and release contains the exact same amount of tracks.
In addition, I can compare this "overall number of tracks" to other informations from external sources like the MusicBrainz Album ID. If this album ID says this specific album has only 16 tracks I can double check it my album is really the correct one.
It isn't enough for me to check if the album is called "Best of". It has to be the "Best of" from this artist with the exact matching amount of tracks too.
It depends on what such a hidden track contains. If it only contains silence and was originally built to get a high number of tracks on the CD to hide the 98th or 99th music track, then my tracklisting looks like this:
01 - First Track.mp3
02 - Second Track.mp3
03 - Third Track.mp3
98 - Hidden Track Name.mp3
99 - [hidden] (if there is no known track name).mp3
I don't save the tracks between 03 and 98 if they only contains silence.
If they are "hidden" but contains any form of music or noise, they will be counted as every other track.
The "overall number of tracks" is 99 (the highest tracknumber) in both cases.
It depends for me as well. But in the cases where many silent tracks are used to hide the last track 98/99 etc, I re-number these to follow the last audio-based tracks prior to the hidden tracks. And TOTALTRACKS then matches the total of the actual music tracks found.
For checking purposes. If the total number of files in any folder does not match the expected total, then I know file(s) are missing from what I originally put there. I can then pull from a back-up, or worst case rip again from the original source.