Yes Eric,
Thx for adding your 2 cents.
When it comes to bluff, Alexander is an un paralleled master. yet, don't forget about one more way to slip away : instead of
41. ....12-17 (or even 9-14, as analysed)
But black could react with
41. .... 23-24,X then 12-17...
the truth is Black had some great expections and were not interested to settle to a mere remise, a that moment at least.

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