Photo of Wait Until Dark taken during photo call:
WYSIWYG rendering made before the set was up or any lights hung.
Using WYSIWYG to render what a show will look like ahead of time really cuts down on time adding or re-focusing or changing gels in lights. Of course virtual will never quite be able to predict everything that shows up in reality, but its pretty close. For Wait Until Dark WYSIWYG allowed me to experiment before I ever got into the space with how shadows would work on stage, as well as show the scenic designer what his wallpaper design might look like with different lighting and contrasts. It also allowed me to communicate ideas with the director that other photos and/or verbal descriptions just wouldn't have worked for.
This rendering was done in WYSIWYG R26 using the shaded view and not the actual rendering wizard, which seemed to not be different enough to warrant the extra time it takes to complete. Some shows this won't work on though, such as sets with shiny surfaces, transparent surfaces, mirrors, etc.. With Cinderella: The World's Favorite Fairytale, which I designed this summer, there were mirrors on stage which necessitated using the render wizard (see example here).