[Retros] PCCC meeting decisions

[Joost de Heer]

http://www.saunalahti.fi/~stniekat/pccc/dec09.htm

For retro-composers the following is of importance:

"The last sentence in paragraph 3 of Article 16 of the Codex was modified."

New article 16:

Article 16 - Castling and En-passant capture

(1) Castling convention. Castling is permitted unless it can be proved 
that it is not permissible.

(2) En-passant convention. An en-passant capture on the first move is 
permitted only if it can be proved that the last move was the double 
step of the pawn which is to be captured [20].

(3) Partial Retrograde Analysis (PRA) convention. Where the rights to 
castle and/or to capture en-passant are mutually dependent, the solution 
consists of several mutually exclusive parts. All possible combinations 
of move rights, taking into account the castling convention and the 
en-passant convention, form these mutually dependent parts. If in the 
case of mutual dependency of castling rights a solution is not possible 
according to the PRA convention, then the Retro-Strategy (RS) convention 
should be applied: whichever castling is executed first is deemed to be 
permissible.

(4) Other conventions should be expressly stipulated, for example if in 
the course of the solution an en-passant capture has to be legalised by 
subsequent castling (a posteriori convention AP).

(Does anyone know what changed *exactly*?)