George Duke wrote on Mon, Apr 1, 2013 11:34 PM UTC:
Most of the re-examination over years has been Moves in the thirties and
Moves in the teens. But by ''post mortem parfait'' 19 e4... is where to
start. It's a defined ''brilliancy'' when White sacrifices a-Pawn
outright. Usually, from Polish Immortal 1929 to Fischer-Spassky Game 6
1972, the correction to reverse the outcome follows soon upon the first
brilliancy.
Http://www.chessgames.com/perl/chessgame?gid=1031957. Finding that right
locus of suspicion, '21...g6' is clearly the unnecessary move. Bad move.
If that is in fact where Black goes wrong, passive Move 21 pointlessly
defending against Knight, what should Black do instead? There still needs be
different improved move at and after Move 21 that likely turns the tide --
to dis-prove this Botvinnik-Capablanca 1938 being perfect game either.