I think it should match.
The width of the <div> in which the thumbnails are placed should be responsible for the number of columns. In my example 3 columns are shown, so I wrote 3 in the theme settings for album thumbnails and image thumbnails. And in the intention to have 4 rows, I wrote 12 as value for "thumbnails on page", which works perfect for albums, that only contain images, albums or both, if the number of sub-albums is divisible by 3.
See here:
http://www.musikverein-zunsweier.de/galerie/waldfest2009/
3 sub-albums, 9 image thumbnails as requestet (sum = 12)
Greetings!
Wete