Not so sure about Fallstreak Holes but I have seen a good few Glories from above in a glider with the glider’s shadow being in the middle (the equivalent of the Brokenspectre).
This is a recent example as I flew close to a cumulus cloud a little above cloudbase on 12th September 2015. Instead of the human shaped Brokenspectre shadow there is of course the shape of the glider, the cockpit being at the centre as that is where my camera / eye is.
-Mike
http://www.flybywire.org.uk/pictures/gliding2015.html is the source of the image.
