No Joost and Stephen: in (a) the bK is not checking the wK - for the same reason the wK…
In fact, in (a) it is double-check (and the Q guards c7). Interesting and subtle difference between this finale and…
Thanks Kjell. Another subtlety might be added: a move whose result is a removing leading to a self-check position is…
Well... it's not all that difficult to understand a piece that changes colour on each move; only the AntiCirce rules…
... with Qb2 replaced with Qa7. Yes, that looks better.
The participants in Andernach this year found the description by Popeye maestro Thomas Maeder helpful: After each move, you check…
The basic mechanism is indeed simple and well-known: it has been known under the German name "Kontrawechsel" since 1938, and…
Thanks Geoff - so “evade hostile observation” has to be taken in the orthodox way. Maybe this fact should be…
No, since in a) the black queen doesn't deliver the check, the black king does.
Popeye's "help anymove" command is very useful for answering such questions. In this case the code is: stipulation h~1 pieces…