I don't see why it shouldn't, Jim. - Do you mean because he has dual monitors or because he uses span mode? - In both cases [Print Scrn] works for me, just the same as it does for a single monitor in 'Single display' mode.
Here's a screen shot in 'Horizontal span' mode of Aqua Garden, made just a few moments ago. And there is one of DA made a few months back, before the recent changes, on
this page.