[Retros] PGs of the Future / Phoenix / Tries in PGs

[raosorio at fibertel.com.ar]

Hi,

I was composing a missed TFPG case (a simple one) and, looking for a quality improvement I realized that 
an obvious usual trick has to be added to the list: Phoenix, PH(X).

There are just 10 PGs in the PDB marked with this keyword, none of them of the future type. Does 
somebody know any antecedent? It looks quite feasible. Of course the PR(X) is a special case of PH(X) but 
we are talking here about the cases where the Phoenix piece ends just somewhere on the board.

But what I consider the strong point here is that PH(X) provides a very suitable base to enhance a TFPG 
with an additional content: a thematic try (I got it with that simple case, a TFPG where a PH(X) is a try).

I personally do like tries in PGs, respecting the original chess problems’ task: to produce paradoxes and to
 surprise the solutionist.  But, what should we consider as to be a try in a PG? 

Some years ago the judge (Michell Caillaud) gave the first prize to Andrey Frolkin in an orthodox retros’ 
tourney, theme Pronkin / Anti-Pronkin.  The diagram shown a very visible Pronkin try but the true solution 
was based on an Anti-Pronkin.  I consider this try as a very nice and subtle content. 

Jorge Lois and I got the 1sr HM in the Kostas Prentos 40th JT,

1.a4 Na6 2.a5 Nc5 3.a6 c6 4.axb7 Qa5 5.b8=B Ba6 6.Bg3 0-0-0 7.f4 Kb8 8.Kf2 Rc8 9.f5+ Rc7 10.f6 Bb5
 11.fxe7 a6 12.e8=B Bd6 13.Bxf7 Ne7 14.Ba2 Qxa2 15.Kf3 Rf8+ 16.Kg4 Rxf1 17.Bf2 Rxf2

Kostas’ theme was “a promoted piece is captured by an officer”; in this PG after 6.Bg3 0-0-0, there is “at 
hand” the Gianni Donati 50th’s try 7.Bb8, Kxb8 which would be thematic, but it fails due to a delay in the
 closing sequence (by the way, this PG shows a double meta-Pronkin performed by bishops, in the sense
 defined in the article “There is no place like home”, Osorio & Frolkin, Strategems oct 2007).

I remember some “sex of the angels” discussions in the Argentine Chess Club referring to tries in #2 
problems. The point was: should a solving line be considered as a try if you don’t “try” it? This applies to 
diagrams where the true solution is more visible than the “tries”, so as a solutionist you go straight to the 
solution.

I would propose the following requirements for “tries” in PGs,

- A try must be structurally feasible, i.e., the required number of moves and paths must be feasible so it fails
 just do to sequence reasons.

- It has to be “easy to see” as a solving line; this would be a quality parameter.

- The highest quality is reached by a “thematic try”, i.e., a try thematically connected to the true solution.
There are a couple of  Lois & Osorio’s pending to appear PGs dealing with this. It would be interesting to 
discuss other antecedents.

Best,
Roberto