Forgive me if I gave offense. If you like clipless pedals, by all means use them. However, you can, in fact, spin with regular old platforms, even without toe clips. The advantage of clipless lies entirely in the fact that they keep your feet from coming off the pedal. The idea that one gets extra power from the upstroke has not been confirmed by any research ever done. In my own experience, clipless pedals are only an advantage in climbing, and even then the advantage isn't huge. On level ground, I can't tell the difference.

http://www.rivbike.com/article/clothing/the_shoes_ruse

Please keep in mind that disagreement isn't the same as a personal attack; I dislike clipless pedals, not the people who use them.