Yeah, ParkinT, but like in life we must play with the cards that we are dealt.
So, rather, lets try this imperfect construct to the cruel semantics and see if it floats...

A card: even (1 in 2) or odd (1 in 2)
Odd number proves statenent wrong.
An even number continues the search.

7 card: consonant (20 chances) vowel (5 chances)
A vowel proves the statement wrong.
A consonant continues the search.

4 card: a vowel proves the statement right because a "b" card has no bearing on the results.

So you see, you MUST turn over the A card first unless you have time to waste which I guess we here all do or else we would be out building bridges or chasing girls or something instead of fretting over puzzles designed to be ambiguous.