That does seem to work well, but isn't a lot of the light "wasted" since it's not aiming directly at the house? It's a great way to keep them dry, though.
I have my Aethers sitting on the ground (we have more rain than snow where I live), and the one to light up my second floor living room window is mounted like this:
Gutter's support members -> Zip Ties -> 12" long 1x4 chunk of rood with 4 drilled holes sitting on top of gutter -> Zip Ties -> Aether