Thinking of problems before falling asleep does sometimes help me in finding solutions in a dream. Though I may still be half awake when doing this.
That may be related or not to the article but Feynman for example wrote a lot about the miracles that the brain can do in the small moments between being awake and being asleep. He thought it unlocked some extra juice and tried to force himself to stay in that moment longer and then to wake up to take notes. You should look into it.
It's a well known technique. I first heard about it from Barbara Oakley, so there is probably some neuroscience research done about it.