[Retros] Fairy retros

[Joost de Heer]

[All answers are my personal views]

On 09/03/2009 08:38 PM, per olin wrote:

> Question 1) why is a proofgame with circe-condition a retro and not a

> fairy problem?


A problem stipulation has 2 classes:
- Type
- Constraints

E.g. an orthodox #2 has as type 'mate' and as constraint 'orthodox'. A 
series-stalemate platzwechselcirce has as type 'series-stalemate' and as 
constraint 'platzwechselcirce'.

For a fairy proofgame the type is proofgame, and the constraint is the 
fairy condition. I.m.o. all problems with type any of the retro types 
(proofgame, release, retractors, etc). belong to the retro section, and 
the constraint is irrelevant.

There are several 'grey areas'. Do reflexmates belong in the selfmate or 
in the fairy section? FIDE albums place them in the fairy section, while 
I think they're closer to selfmates in nature. Should stalemates belong 
in the same section as direct mates?


> Further questions: Question 2) what is the definition for

> retroanalytical problems?


Its main content is retro-based. E.g. legality questions for Proca
retractors, regardless whether it's orthodox or fairy. There have been 
numerous discussions whether proofgames should belong in the 
retro-section. For now, lacking a better category, it belongs there.


> Question 3) what is the definition for fairies?


The type is non-retro and the constraint is not orthodox.


> Question 4) should retros (and many of the other groups) have a

> subdivision g1)orthodox retros and g2)fairy retros?


Perhaps. But then you'd probably end up chopping the category in 315
subclasses. For how can one compare proofgames with retro-rebuses?

I think that the fairy composition of Peter Harris belongs in the fairy 
column, because I have a strong feeling that the rectractions have 
nothing to do with legality (I haven't solved this composition, nor am I 
interested in solving it to be honest).

Joost