|notyetagm: Position after 60 g5xe6!:
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60 g6xe5! is possible only due to the <BALEFUL INFLUENCE> of the White f8-bishop against the <UNDEFENDED> Black a3-knight through the Black d6-pawn.
<<<You do not want -anything(!)- of value (<LMS-TARGETS>) to be on the line of your opponent's line pieces!>>>
And if you cannot avoid this rather severe tactical liability, then you must be -extremely- careful that you do not <OVERWORK> one of your pieces by having it <BLOCK THE CORRIDOR> of the dangerous enemy line piece while at the same time <DEFENDING> a square.
Here, for example, the Black d6-pawn must meet the threat of f8xa3 by <BLOCKING> the diagonal a3-f8 while this Black pawn also meets the threat of g6xe5 by <DEFENDING> this square. Hence the Black d6-pawn is <OVERWORKED>, since it cannot meet both threats all by itself.