It appears the issue I have is related to the use of an ampersand in folder names. “Assets” of albums become associated if those albums folder have an ampersand in their name and they are located in the same folder, an artist folder or composer folder for example. Also, it appears, album assets can become associated if those album folders are all located in a folder with an ampersand in its name. This does not appear to be related to the name of the album itself (the album tag) or the file name of the asset.
Not sure if this is by design. If so, it might be covered better in the WIKE somewhere. Otherwise, be advised that using an ampersand in folders introduces some interesting folder math.