The tone of the document is all wrong. It reads fake as hell to me.
I have received an ***unverified*** report from an otherwise reliable source, which is purportedly from Mt. Gox. The document, which is titled Crisis Strategy Draft outlines the current situation at the exchange.
So the document is a "Crisis Strategy Draft" from Mt. Gox itelf.
Goxs own workaround solution was criticized, and eventually a fix was provided by Blockchain.info. The truth, it turns out, is that the damage had already been done. At this point 744,408 BTC are missing due to malleability-related theft which went unnoticed for several years.
But, they're using language like "Gox's own workaround" which implies that the author is outside the Gox organization. "The truth it turns out" is not something someone would write in an internal document. Also none of this is a "Crisis Strategy".
Do not believe.