Perhaps it can get really high when you're new to it like the games ratings. Probably not but thought i'd say something regarding the chess.com algorithms. No point in cheating puzzles really though. They're a way to practice so not sure why anyone would want to cheat.
Puzzle Hack?
I think the main problem isn't the rating, anyone who dedicated enough time could solve any puzzle given they know the rules of chess. I think the real thing that gives it away that it is probably a bot/cheat is the sheer amount of puzzles solved. Currently the two highest puzzle rated profiles are AriesGen and GenAries, each with a lot of time dedicated to puzzles (one has ~97 hours, the other ~1170 hours). So if someone has played decided "Hey I'm going to memorise every puzzle rated 2800 and above so that it becomes easy for me!" that runs into 2 massive issues, 1) they actually have to memorise the puzzles and, 2) they have to do the same puzzles hundred of thousands of times over. It takes the current top/second top player ~10 seconds per solve, lets assume they can recall puzzles perfectly (incredibly unlikely by the way, but not impossible), and they can input the solution in perfectly (no misclicks, ect), they have to sit down and play the same puzzles over and over and over again. Hundreds of repeated puzzles and hundreds of hours. It isn't impossible but it is definitely suspicious. Other than assuming all this stuff we could just assume that someone who knew just a bit of coding decided they were going to cheat. Which one sounds more reasonable?
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