Reasonable to question CPL of opponent?

Question about the CPL of my last opponent. Would it be reasonable to question them having an ELO of 1398 and the after game review shows that they played at around a 2150 ELO and every one of their moves were the best move according to the review? After that I also did a second analysis with a separate engine analysis board and that one showed only 1 move they made as mistake but it also said every other move was the best move as well as showing my opponent having a CPL of 14.

Is it out of line for me to be feeling questionable of that or am i not thinking from an accurate perspective?

there are lots of scenarios that can legitimately lead to that result. Short games, the one line in their favourite opening they know best, etc. but if you suspect someone you can request the moderators check.

also, this sounds like a chesscom question - game review, Elo, performance rating, and "best moves"

Are you sure you are asking on the right chess website?

@QueenRosieMary said in #3:
> also, this sounds like a chesscom question - game review, Elo, performance rating

I agree but I should point out that chesscom, contrary to popular belief, doesn't use Elo (or... "ELO" *shudder*) so that term is no more appropriate on that site than this one.

@AsDaGo said in #4:
> I agree but I should point out that chesscom, contrary to popular belief, doesn't use Elo (or... "ELO" *shudder*) so that term is no more appropriate on that site than this one.

Nothing wrong with a bit of Electric Light Orchestra though.

@AsDaGo said in #4:
> I agree but I should point out that chesscom, contrary to popular belief, doesn't use Elo (or... "ELO" *shudder*) so that term is no more appropriate on that site than this one.

If I can dial a phone that doesn't have a dial, or film a movie without using film, maybe it's okay to use Elo in its metaphorical sense.

@QueenRosieMary said in #3:
> also, this sounds like a chesscom question - game review, Elo, performance rating, and "best moves"
>
> Are you sure you are asking on the right chess website?
From lichess discord we got chess.com questions now here!
lol

Elo is word for rating. The meaning of rating point is same FIDE Elo rating algorithm, Glicko-1, Glicko-2, Bayes-Elo, Universal Rating System....

It different from original ELo from his book but in so minuscule way that for all practical purposes: All rating systems used in chess estimate Elo points just by different maths to come into same conclusions eventually.

Those metrics by themselves are not sufficient for cheat detection. I will link to another post I made, to not repeat it all over again: lichess.org/forum/general-chess-discussion/i-am-tired-of-this?page=2#19 - if these criteria are checked, it's much more likely that it's a cheater.

It is normal for sub-10 ACPL in very decisive, shorter games where one side gets a winning advantage very quickly via tactic, and the rest is just some conversion/mating attack - often the ACPL for those moves is always 0 even if the best move is not selected since the computer thinks everything is winning.

Also chesscom "performance" rating and "best moves" etc is just a tactic to make players feel good about themselves. Would not put too much stock into it.

@crtex said in #9:
> Also chesscom "performance" rating and "best moves" etc is just a tactic to make players feel good about themselves.
I think Lichess ratings are a tactic to make players feel good, they are so bloated up....