moriador, "I find very, very few renders of poser people to look particularly real. There are too many things standing in the way"

That is not any special just for Poser. 3Ds max, Maya and C4D or any computer software inclusive Renderman and Disney studios have this problem. There is one one way to do it and that is by postwork. Like addy do and a few others.
<a href="http://www.renderosity.com/mod/gallery/index.php?image_id=1189652&user_id=122068&page=3&member&np">realistic Poser figure

So the great majority doesn't even bother to try... That is what I find rather - sad.