Interesting, I used to do almost the exact same thing a few years ago. Except I counted down from 15, and physically tapped my foot against the bed on each count.

If memory serves, I stopped this practice after messing up enough times that I realized I could sleep in a little longer with my schedule, and now I get up a full 30 minutes after actually "waking up". I think I'll reimplement this and see if it affects my sleep-in habits. (Publicly announcing something also seems to work about 60% of the time for me.)