Bah. I’m ready to throw in the towel on this one.
I’ve got a system with intel integrated video. Sax was playing some funny games, but finally I was able to get the system configured almost perfectly. I had the virtual space set up, LVDS and VGA running at the right resolutions, and quickly and easily configuring the output using xrandr.
BUT! Apparently it seems that Intel will force the VGA to always be the primary monitor. That’s fine if I connect to a projector, but at my desk I really want the LVDS to be the primary display.