Did Crafty make an illegal move, or is cutechess dumb?

[hgm]

I don't quite get this answer, or do I miss something? Both rook moves for Black are legal.

In that case disambiguation comes from "+". I think this is the idea.

P.-S. But here is what the PGN specification says:

Neither the appearance nor the absence of either a check or checkmating indicator is used for disambiguation purposes. This means that if two (or more) pieces of the same type can move to the same square the differences in checking status of the moves does not allieviate the need for the standard rank and file disabiguation described above. (Note that a difference in checking status for the above may occur only in the case of a discovered check.)

Oh, sorry, I misunderstood the problem. Indeed, the fact that a move delivers check should not be considered to disambiguate it.

[Guenther]

Note also that the pgn says 'Crafty 18.0', which is from the end of year 2000 or very early 2001!

Yet age appropriate for the computer it is running on, if you notice. It is Stockfish who is being transported back in time.

Hi John,

I only mentioned it because this already raised the chance for a bug in Crafty and made me curious to verify it ;)
And yes I saw the nodes limitation for SF.

BTW I always read your posts with pleasure, because IMO you are one of the few remaining sane and interesting voices here.
You should feel encouraged to post more here in talkchess.

Guenther

[AndrewGrant]

TLDR: I was right? Big if true.