The book How Purdy Won, starting on page 37, gives Purdy's notes to his game against M. E. Goldstein (White) from the inaugural Correspondence Championship of Australia, which started in 1937. The following position was reached after 21...Q(c7)e7:
Purdy writes, "If 22 Re3, Kh8 followed by ...Rg8, etc."
However, after 22. Re3 Kh8 23. Rh3, 23...Rg8 would allow 24. Qxh7+! Kxh7 25. Nf5+ Kg6 26. Nxe7+ Kg7 27. Nxg8 Kxg8, when Black lacks sufficient compensation for the exchange. (See next diagram for this sequence.)
I had first thought that after 22. Re3 Kh8 23. Rh3, Black could play 23...Bxg4, intending to meet 24. Nf5 by 24...Bxf5 25. exf5 Rg8+ 26. Kf1 (26. Kh1? Qb7+ 27. f3 Rb1+) 26...Rg7. Then I realized that 23...Bxg4 would lose a piece after 24. Rg3! Rg8 25. Kh1 followed by 26. Rag1 and then 27. Rg7 if the bishop flees. But the silicon analyst brought to my attention that after 25...Qe6 26. Rag1 Rbb8 (unpinning so that 27. Nf5 could be met by 27...Bxf5 28. exf5 [28. Rg7? Bxe4+] 28...Qxf5 29. Rg7 Qf3+) 27. f3, Black would emerge with three pawns for the piece by 27...f5! 28. Qxe6 fxe6 29. fxg4 fxe4, which seems about equal. (See next diagram for the sequence in bold.)
White actually played 22. Nf5 (instead of 22. Re3), and a draw was agreed after 22...Bxf5 23. gxf5 Qf8.
@FMDavidHLevin
Nice to see someone doing some quality analysis. Pretty interesting.
Keep up the good work. 🙂
'Purdy writes, "If 22 Re3, Kh8 followed by ...Rg8, etc." The infamous 'etc...'
which used to be potential fishing grounds for research and exploration.
These days 'etc...' has been replaced by something like ⩲ or ∓ or a number
and unless it was done by an acient computer set on a low horizon then
there is not much chance of finding a tactical smash like 24. Qxh7+
Some lad thinks he should avoid the Purdy book. I think it's all the more
reason to pick one up if you see it going at a reasonable price. Not only will
you get dozens of Purdy gems (see below for just a few) which have entered
chess lore. These pre computer books are excellent work books to stop you
from sitting there and 'reading and nodding' as Nigel Davies puts it. You will
have to put some work in which will be benefical and increase your enjoyment.
Just a few Purdy quotes.
'Pawn endings are to chess what putting is to golf.'
'If the student forces himself to examine all the moves that smite, however
absurd they look at first glance, he is on his way to becoming a master of tactics.'
(from which I coined my war cry: 'Check all Checks!)
'Chess players may be divided into three classes: those who don’t know the
principles, and are therefore very weak; those who know the principles and
are less weak; and those who know how weak the principles are, and are strong.'
I don't expect annotators to be perfect. I very much like Bronstein's book on Zurich 1953 even though I found analytical mistakes in it.
But finding these mistakes in Purdy's annotations disappoints me because (1) he played the games, and (2) they were by correspondence, both of which tend to give someone a deeper understanding of the play than if an annotator were a third party.
And I didn't spend hours laboring on a game to try to find a hole. I played the games out on a board and visualized the play given in his notes. I'd consider myself a fair tactician, but he was a national crossboard champion and a world correspondence champion, so I don't think my expectations are unreasonable.