  A currently discussed interpretation of quantum theory, Time-Symmetrized
Quantum Theory, makes certain claims about the properties of systems between
pre- and post- selection measurements. These claims are based on a
counterfactual usage of the Aharonov-Bergmann-Lebowitz (ABL) rule for
calculating the probabilities of measurement outcomes between such
measurements. It has been argued by several authors that the counterfactual
usage of the ABL rule is, in general, incorrect. This paper examines what might
appear to be a loophole in those arguments and shows that this apparent
loophole cannot be used to support a counterfactual interpretation of the ABL
rule. It is noted that the invalidity of the counterfactual usage of the ABL
rule implies that the characterization of those outcomes receiving probability
1 in a counterfactual application of the rule as `elements of reality' is, in
general, unfounded.
