Natch switch (was Re: [Retros] Two little SPG-challenges)

[CAILLAUDM at aol.com]

Hello,
 
The current record for the difference is 4.5 moves, with the 2 existing  
examples composed by Gerd :
 
1)
3rd HM U.S.Problem Bulletin 1995-97
r1bq1b1r/pppppkpp/4Rp2/3P3n/5PQ1/6P1/PPP1NKP1/RNB2B2
a) SPG in 8.5
b) PG in 13.0
 
2)
Probleemblad 2004
1rbqkb1r/ppppp1pp/n4p2/8/2BQn3/8/PPPNN1PP/R1B1K2R
 
a) SPG in 7.5
b) PG in 12.0
 
Best,
 Michel



The  aforementioned problem by Gerd Wilts

> from Die Schwalbe 1994, recently  awarded a 3rd Honorable Mention

>  rn1q1b1r/ppp1pbpp/4pp2/1k5n/7P/4P3/PPPPKPP1/RNBNQB2

> a) SPG in  10.0

> b) PG in 12.5


was - according to the comment in the award  - the first counter-example
to the thesis, that the difference k for a  position, which has both a  
unique PG in N and in N+k moves, can't be  larger than 2.

Does somebody know what the current record for this  difference is?




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