Practical Advice on Open Files From Purdy

     C.J.S. Purdy, an excellent analyst and one of the finest writers on chess ever, in annotating the following game gave some excellent instruction on open files. 
     Cecil Purdy won the first world correspondence championship in 1950-53, but Chessmetrics lists his OTB high rating at a modest 2346 on the June 1980 rating list.  It's hard to say how accurate that rating really is though because Purdy never played in any European tournaments and so Chessmetric's rating is against opponents mostly from Australia and New Zealand. In 1946 Purdy held Tartakower to a draw in a radio match and in 1947 he drew with Harry Golombek, also in a radio match. 
     Purdy's last tournament was the Sydney International held in 1979 where the 73-year old finished in last place (out of 11 players) with +2 –6 =2.  The event ended in a tie between Raymond Keene and Ian Rogers, both of whom dominated the event, scoring an undefeated 7.5-2.5. Purdy passed away shortly after the tournament. 

     Purdy observed that a single open file will often result in a drawish position because the heavy pieces are likely to be exchanged on it which normally leaves a balanced minor piece ending. And, any attempt to win such an ending is likely to involve taking risks. 
     He stated that if you are trying to win, then you have better chances by opening a second file. That's because a 12 Pawn vs. 12 Pawn ending is more likely to create winning chances than a 14 Pawn vs. 14 Pawn ending. He also added that bringing about the second P-exchange necessary to create the second open file without compromising your position can be difficult as seen in this game.
     In this game, as usual, it turns out that analyzing with a strong positionally-oriented engine like Komodo 8 some of Purdy's observations will turn out to be questionable, but that's not important. What's important, unless you are playing engines or world champion caliber players, is ideas. You can use the ideas in your own games to develop a reasonable plan and create winning chances. WGM Natalia Pogonina addresses the subject of open files in more detail on THIS Chessdotcom article.