Bi - Wire Cable Usage

Creative thinking, however I would not chance it given the possibility some conductors cross over internally between the two sets of spades. I am guessing most reputable cable makers would have consistency between sets of spades, but I wouldn't bet on it. 

A bit of experience and advice to get you an even better result. Use the bi-wire cable as one cable; parallel the spades to make one pair of pos/neg at each end. Pursue a second set of speaker cables, and use them for the other set to bi-wire. Ideally you will want the same brand, and if possible the same model, of speaker cable as the second set. 

The result will almost assuredly be better in every respect sonically. If the cables are different brand/model, you can switch the cables between bass and mid/tweet to find which sounds better to you.  :)