So here I am, banging my head against the table repeatedly (quite literally, feel free to ask my colleagues) because of a bug so idiotic I can't even begin to describe it.

I wasted 20 minutes tracking down a bug just to find what Rik Hemsley says best:

?productlistview.Items(0).Selected
True
?productlistview.SelectedItems.Count
0

Hmm?

Apparently, though no-one will tell you this, the selection could fail if you don't have the focus. Make sure you add a call to lstWhatever.Focus() before you mess with selections.