Speaker Cable directionality: reversable??

Shielded speaker cables ? Are you sure you're not confusing them with interconnects ? Why on earth would anyone shield speaker cables ?
My personal opinion : wire is not directional. Interconnects may be directional, due to shielding only being grounded at one end.
Speaker cable directionality is nonsense UNLESS there's some sort of network box on the cable (MIT does this I think). It's an AC signal ... that means it goes equally in each direction.

HOWEVER ... if it bothers you then just hook them up in the direction indicated and leave them alone. Why even bother to try them in the "wrong" direction, other than to satisfy your curiosity ? And you can't satisfy your curiosity by asking our opinions .. you'll only do it by experimenting yourself. (Which I have done, just to see if it does make a difference ... I certainly couldn't hear any).

If I were you I'd hook them up in the "correct" direction and then leave them alone and enjoy the music. I'm certain that they're not directional, but from your question I just know it's going to play on your mind if they're the wrong direction. Sooner or later you'll end up changing them.

Oleander .. sorry for the misunderstanding ... you can get banana-spade adaptors, as other posters said.
You seem to have replied without reading my post .. if you hook them up the wrong way around won't you always be a bit curious as to whether it would sound better the "correct" way ? Won't you end up switching them around eventually, just to see(hear)? I think you will since you started this thread, so it shows that you're concerned about it, and I doubt advice on this thread will completely put your mind to ease.
So my advise was to put them the right way around now, whatever it takes, or else it will just play on your mind that "perhaps the sound could be better".

I don't think it will make any difference, but does my opinion really convince you to the point where you don't need to try it for yourself ?

Twl .. phasing of speakers is done so that the cones don't move in opposition, causing cancellation. How can wire possibly have a similar effect ?
Bob .. your answer is interesting, but I have yet to hear any difference for myself, so perhaps, even though the crystal structure of the wire might not be completely even due to the drawing process it's probably a third or fourth order effect (after inductance, capacitance, resistance etc etc) and so not really worth worrying about.

Bob .. I think you'll find that most "naysayers" would like a good explanation. I'm a naysayer because

1) I was not able to hear a difference with "directional cables". None whatsoever. I do believe that cables themselves make a big difference, so don't immediately brand me a luddite.
2) Nobody has given me a good explanation. Rather the believers are as much to blame as the naysayers for making this a "religious" argument based on faith in their own listening abilities, and half explained pseudo-science.
3) The cable industry is so full of (dis)information because there's tons of money to be made from gullible people.

I find your argument about power totally unpersuasive. Sure power is dissipated in the speakers ... so what .. how does that make a piece of wire directional ? Give me a good explanation (or an HTTP) and I'll stop disagreeing on this issue.