First things first, thank you so much Zybex for taking the time to answer these questions - you truly are one of the most helpful users on the forum.
Unfortunately, neither of the expressions work for me. Both expressions yield the exact same result as shown in the 1st picture below (same album/track count for every artist). For the record, the current actual values are ~ 1000 artists, 2249 albums, and 26,750 files/songs.
I spent some time tweaking around the edges with some slightly different approaches, but nothing worked. Interestingly though, when I use the expression below that Marko created (found on an old thread) for thumbnail text, I get exactly what I want (as shown in the 2nd pic):
<b><font size="130">[Artist Sort]<//font><//b> if(isequal(groupcount(album),1,5),/(groupcount(album) Albums/),/(groupcount(album) Album/))
I figured if I used the above expression for the TREE and expression column, it would solve the problem, but no luck there either. I did not make additional pictures for this post to show it, but for the TREE, it again shows every artist has only one album. For a detail list, it also shows the same number of albums for every artist, but instead of 339 for every artist that I got using your expression(s), it shows 32. Also interesting though, is if I use your expressions as thumbnail text they also work perfectly. It just won't work in the TREE list, or in a LIST list.
I am completely flummoxed. If you have any ideas or guidance, I would greatly appreciate it!