[Retros] Retro_snippets_001 - Schnoebelen Promotion / the Pawn case

[Joost de Heer]

raosorio at fibertel.com.ar wrote:

> Dear friends,

> Here follows an antecedent of Pawn Schnoebelen,

> 

> Roberto Osorio - RML february 16th 2006

> rnb2bnk/pppp1p2/1q1p4/8/7p/2N5/PQP1P1PP/R1B1KBNR

> PG in 22 single moves Singular on GOS>>

> ----------------------------------------------------------------------------------

> Solution,

> a) Stipulation: single box type II

> b)sequence:

> 1.- d4,h5 2.- d5,h4 3.- d6,exd6 4.- f4,Qf6 5.- f5,Qxb2 6.- f6,Qb6

> 7.- f6xg7,ke7 8.- g7xh8,Kf6(h8 can't be bishop or queen)

> 9.- Qd4+,Kg6(h8 can't be a knight) 10.- Qb2,Kh7(h8 can't be a rook)

> 11.- Nc8,Kxh8 (Schoenebelen pawn).


SB doesn't work that way. A pawn stays a pawn until a piece X is 
captured. Only then it's replaced by X. There's no 'looking back' to see 
if the black king would've been in a selfcheck were that pawn piece X.

1. f4 d5 2. f5 d4 3. f6 d3 4. fg7 dc2 5. gf8 Qd3 6. ed3 Kd7 7. Ke2 
cd1=B[wQf8] is a perfectly legal sequence in SB II. After whites 5th 
move, ed1=B is an illegal move however (selfcheck).

Joost