For instance, a recent post advocated installing really bright lights as a way to boost alertness and productivity. We should not adopt such hacks into our dogma until we're pretty sure they work

Why's that? Please remember the value of information here! Bright lights cost very little either upfront (maybe like <$100?) or on an ongoing basis (higher electrical bill), while an experiment may be very costly (or so I infer from the near-absence of anyone but me doing randomized self-experiments), and the benefits cumulatively large over the X years a bright light will last before breaking or burning out; hence, the best course may be simply to try it out.