Yes, but what the heck -- I tried it again. Uncheck...restart. Check...restart. Nope. I held the phone upright and waited patiently (not my best thing), and eventually, the little eye-ball looking icon showed up on the notification bar, as if to sak, "Is anybody there?" The screen then dimmed and then went blank.
Hold it in a natural way that you would use the phone. I noticed that if I tried these features on previous Galaxy S devices, they didn't work well, but they worked much better when I wasn't "trying" to make it work and just used the phone normally.