Here is the latest flash on the possessive poison front. MGMAT , the originator( Am I right ) of this thesis has stated:

!. i'm pleased to announce that we are strongly considering eliminating altogether the coverage of "possessive poison" in the next forthcoming edition of our strategy guide.
while this rule has been mentioned in the answer keys to one or two official problems, it has never been dispositive in even a single problem, and it has caused confusion vastly outdoing its usefulness for a great number of students.( RON)

2. by the way, this "possessive poison" rule is much more trouble than it's probably worth. you can occasionally use it to eliminate a choice here and there, but it has so far been decisive in a grand total of ... wait for it ... ZERO official problems. none.
ever.

furthermore, the newer edition of the OG verbal supplement doesn't even posit this rule anymore! compare the answer key for #86 in the 1st edition OG verbal supplement (theonly place where this rule has ever been mentioned in an official publication) to that for #81 in the 2nd edition (in which all traces of this "rule" have mysteriously disappeared from the explanation).( Ron)

It looks as if GMAC itself has given a decent burial to this dreaded rule. Do we need to bother any more?
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