I think I agree with most of the article and that it applies to most games, not just puzzles. Also some interesting comments in the original link.
“When I started constructing crosswords for the Times, friends began to ask me what constitutes ”cheating“ when you’re solving a crossword puzzle. I’m not sure why making the puzzles (or even being a regular solver of them) renders me an expert, but I’ve tried to supply answers over the years, and I’ve gotten to the point where I have a usual response that I’m comfortable with.[…]
To put all of that in a nutshell, I think a good rule of thumb is that you should do whatever research doesn’t make the puzzle trivial. If it’s a ”What do these things have in common“-type puzzle, then don’t just google the list. If it’s ”Who won the Best Supporting Actor Oscar in 1975“ (which I promise never to ask), don’t go to the IMDb’s list of Oscar winners. Etc.”