[Retros] Troitzky masterwork no.1

[Pascal Wassong]

Hello,

retracting these moves lead to an illegal position, in the south-east
corner.  The presence of the bNh1, blocked by wPf2 and g3, prevent the
wRh1 to return to its homesquare.

Best,
Pascal

>>>>> "John" == John Tromp <john.tromp at gmail.com> writes:

  John> I have a question about the solution at
  John> https://www.janko.at/Retros/Masterworks/Solutions.htm#1

  John> Why couldn't the last moves have been

  John>          d7xc6+ Kb5-a5 Bc8-g4 f2-f3 o-o-o f3xg4 Qh6-h5+ g4xh5
  John> Rd8-d6 g3-g4 Rd6-h6 g4-g5 g7-g6 g5xh6 g6-g5

  John> leaving white without a win?

  John> regards, -John