Hahah yea man that video blew my mind! I was like
OOOO for the rest of the night the first time I watched it.
The compositing breakdown video is pretty interesting to see how he put it all together. I was surprised to see how much of the lighting was handled in post, but I suppose it's easier to control and faster to get feedback that way.
I haven't tried out mr proxies at all, haven't really had the need to yet. I think I might just try some crazy big scene that requires it though, if only to test the limits of my lowly CPU.