A currently discussed interpretation of quantum theory, Time-SymmetrizedQuantum Theory, makes certain claims about the properties of systems betweenpre- and post- selection measurements. These claims are based on acounterfactual usage of the Aharonov-Bergmann-Lebowitz (ABL) rule forcalculating the probabilities of measurement outcomes between suchmeasurements. It has been argued by several authors that the counterfactualusage of the ABL rule is, in general, incorrect. This paper examines what mightappear to be a loophole in those arguments and shows that this apparentloophole cannot be used to support a counterfactual interpretation of the ABLrule. It is noted that the invalidity of the counterfactual usage of the ABLrule implies that the characterization of those outcomes receiving probability1 in a counterfactual application of the rule as `elements of reality' is, ingeneral, unfounded.
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