Hey man cool stuff. I've written such reminders and find that they do help. Try not to get too obsessive about it tho : D

P.S. I wouldn't be so sure about being unable to feel pain in lucid dreams either, I have felt pain in dreams personally. Loosening your general perception of lucid dreaming broadens your prospective range of experiences. Preconceived notions generally only limit our acceptance of reality [and thus lucidity] and create barriers.

Happy dreaming!