That sounds like a very encouraging summary. Presumably when interpreting the law the judges have to use as their guiding principle the "intentions of Parliament" -- and it is surely plausible to say that the "intentions of Parliament" cannot have been to systematically disadvantage women??
Likewise the "intentions of Parliament" cannot have been to generate outcomes that are literally incoherent.
So hopefully this all tends towards the judges concluding that Parliament must have intended to preserve the ordinary understanding of sex - at least as the default where it is not (to a sufficiently explicit standard) stated to mean something else??
EDIT: Is it correct to say that the "intentions of Parliament" are the crux for interpretation? I would clarify that IANAL, except that, to me, that looks too much like saying "I am anal"