Reasonable conclusions
Repeated observations may show that a particular light schedule makes awakening more tolerable in one bedroom. A separate trial may show that guided focus practice helps the same person begin a defined task with fewer prompts.
A null result is useful when conditions were documented. It can reveal that the intervention missed the actual problem, demanded too much effort, or produced too little benefit to justify daily upkeep.
Questions the devices do not settle
Neither category can determine why someone has persistent daytime sleepiness, declining attention, or major functional difficulty. Consumer observations may help describe a pattern, but they do not establish its medical, psychological, or environmental cause.
New confusion, dangerous drowsiness, severe mood change, vision symptoms, or a rapid decline in ordinary functioning warrants appropriate professional attention instead of repeated device experiments.