Rules that you misunderstood when learning (or were a kid)

[IM Jack Rudd]

There are some exceptions to that, such as Rxh2 immediately losing the rook back to ...Bxg3+ or something, but yes, it's much more niche.

[Geoff Chandler]

Hi Jack.

Can think of dozens examples of Rxh2 sac v a castled King but not with a white Rook on h1 and being answered with 0-0+

The bares bones of the idea (imagine more bits on the board) would have to be something like this.

[FEN "7r/5k2/8/8/8/q7/6PP/4K2R b K - 0 1"] 1... Rxh2 {Intending to answer 2.Rxh2 with Qg3+} 2. O-O+ *

[Stewart Reuben]

Ke1; Ra1; Rb1, Re8. black kh1. White's last move was Pe7-e8=R.
At one time White could deliver mate in one by castling. Moving the Ke3 and R on e8 to e2. The spoil-sport Rules Commission stopped that by tightening up the castling Law.

[John Clarke]

Kevin >No checks allowed. simples<
Of course that is incorrect.
You are allowed to castle giving check.
Not allowed to castle when in check.
Not allowed to castle through check.
Not allowed to castle if the king, or rook involved, has moved.
I will leave you to realise what other rules I have left out. Anyway, why don't we call it 'rooking'?

Not allowed to castle into check. Nor where there are pieces of either colour on the intervening squares.

[John Clarke]

There was an article from the woke nutters saying something about it's unfair that White always goes first in chess and it should be changed. Don't suppose anyone pointed out that the players take turns to be White.

Surprised those nutters haven't queried why White always wins in problems or studies, or (by drawing) succeeds in frustrating Black's attempts to win. George Orwell posed this question over 70 years ago in the closing passages of 1984.

[John Clarke]

Surely the most common problem is lack of understanding of the EN PASSANT rule. I certainly never teach it to beginners and often come across players who may have been playing for a year without having encountered it.

I did my BCF(sic) Regional Coach's course under Bob Wade who advocated teaching beginners the 'pawn game' first. All pawns on second rank as usual, first to get a pawn to the eighth rank wins. Thus 'en passant' is an important concept and can be taught as soon as it crops up.

I agree totally. People usually go on about how tricky the knight's move is, but it's the pawns that are the really awkward little buggers.

[John Clarke]

One computer program back in the sixties omitted to specify that when a pawn is advanced two squares in its first move, the intervening square has to be vacant. Has anyone ever encountered this misunderstanding in OTB?

[Stewart Reuben]

Paul Habershon > Bob Wade who advocated teaching beginners the 'pawn game' first.<
I guess that is fine when a child follows a chess course and has no outside input. I have seldom taught children in this manner. One lesson and they went out into the world, possibly coming back a few days later.

[Roger de Coverly]

One feature that even experienced players may misunderstand is that draws by threefold repetition refers to positions rather than moves.

[Stewart Reuben]

Roger > may misunderstand is that draws by threefold repetition<
It is NOT three fold repetition. It is threefold occurrence. Threefold repetition means the position has occurred FOUR times.
e.g. 1 Nf3 Nc6 2 Ng1 Nb8 3 Nh3 Nh6 4 Ng1 Black is entitled to write down Ng8 and claim a draw.

[DavidGostelow]

There was an article from the woke nutters saying something about it's unfair that White always goes first in chess and it should be changed. Don't suppose anyone pointed out that the players take turns to be White.

Dont you play with the new rainbow sets

[JustinHorton]

The use of "woke" almost always indicates "I'm a stupid raging old clown looking for a nothing story to get outraged about" and this incidence is clearly no exception.

[Neville Twitchell]

Roger > may misunderstand is that draws by threefold repetition<
It is NOT three fold repetition. It is threefold occurrence. Threefold repetition means the position has occurred FOUR times.
e.g. 1 Nf3 Nc6 2 Ng1 Nb8 3 Nh3 Nh6 4 Ng1 Black is entitled to write down Ng8 and claim a draw.

The three-fold repetition rule, or as Stewart more correctly says, the three fold occurrence rule is one that harbours numerous opportunites for misundestanding. I was caught out early in my chess career by playing the move that brought about the repetition rather than merely writing it down and declaring my intention to play it, thus having my claim disallowed. Another point is that, of course the position has to be dynamically as well as statically the same, so that if castling were possible the first and/or second time and not the third it is not a repetition, and likewise if en passent were possible the first and/or second time but not the third it is again not a repetition (thereby compounding possible confusion over the repetition rule with confusion over the en passent rule). Also, there is probably a misconception among some players that the repetition of the position has to occur on consecutive (or, if you like, alternate) moves whereas of course they may be separated by many intervening moves.
The fifty move rule is another that is often misunderstood, particularly since I know it has been extended to 75 moves for certain endings where it was discovered you could force a win but that it might take more than fifty moves (viz K+R+B v K+R). I am not sure if the 75 move rule had now been rescinded, and whether it has ever been tested in practice..

[John Clarke]

Re threefold occurrence/repetition: don't forget that as well as castling rights, en passant, etc, the same player has to be on the move each time. Ray Keene once snaffled a win (at an Olympiad, I think) by allowing his opponent to declare his intention of bringing about a third occurrence by playing such-and-such a move. Unfortunately for the opponent, it had been Ray's turn to move on each of the previous occasions, so the claim was dismissed and the game continued. But the real kicker was: having declared his intention, the opponent then had to actually play it, significantly worsening his position. You can find the game here. Ray tells the story in his notes (and there was a lot of other to-do around the game as well, as you'll see).

[Roger de Coverly]

The fifty move rule is another that is often misunderstood, particularly since I know it has been extended to 75 moves for certain endings where it was discovered you could force a win but that it might take more than fifty moves (viz K+R+B v K+R). I am not sure if the 75 move rule had now been rescinded, and whether it has ever been tested in practice..

Extensions to seventy five moves were abolished many years ago when tablebase analysis became widely available. The position now is that regardless of whether a tablebase says it's a win, if you have to go fifty moves without a capture or pawn move, then it's a draw.