Why do you think Bi-Wiring improves the sound ?

No it doesn't necessarily work for those who have tried it. I've had bi- wired speakers never made any difference there's no reason it would.

I wont even comment on the benefits of bi-wiring, + or -.  I have my biases and i have not done it it too long to feel confident.

But i will say that Millercarbon's comment is the most important one that we should all keep in mind, and almost no one ever asks.Many things work. The question is always "where can i get the most benefit for s given expenditure"
Right now i am placing most of my effort and money on sources (DAC, low jitter/noise sources, cartridge) and on room/setup. The sound, as it sits, is frankly amazing so I'm not out to change any fundamentals. 

I believe most people can get the biggest changes from setup, room and source material (e.g.: the best recordings).  Oh, and i make (or more accurately have and will) the costly electronics stuff i'm down-playing :-)
The great thing about bi-wiring is that with many speakers you can do a low-cost test -- even if the test is with lesser cables than the ones you own.  This way you can separate two effects:  a) wire sound (if any) and b) bi-wirign affect (if any).
G

As for kool-aid  It worked for the Grateful Dead !

Well, that kind of kool-aid may improve the sound of any system. I know for a fact i prefer the sound of my system after a glass of good wine or Scotch.  really.

I go by the fact that if some speakers have the capability, then why not use it in that manner (biwired), can’t hurt...the speakers with just one set of terminals, well then, I have nothing to fret about as there is the one option. I can’t say that I’ve heard an astounding difference, if any, in sound quality, but I’ll use the speaker in that manner if the design allows. Plus I’d rather biwire where applicable rather than use the crappy metal jumpers provided any how.

Not that it would directly pertain to your situation, but simply improving the jumper situation can have a noticeable improvement...or change, rather. I say this for perspective, as I would not conceive of going to the trouble of changing a crossover to add extra posts. Just improving the crossover with better wire/connections, caps, resistors alone should be more than sufficient. I’m sure I’ll receive some flac for suggesting this, but would it not seem that a biwire configuration would be taking into account cabinet and driver design? Some of the very best speakers out there only have one set of posts. But my current speakers (totem arros) have two sets, and when I simply changed out those factory brass honkers with silver plated audioquest wires...wow, a real improvement (to my ears, anyway). So maybe just some improvements to the existing crossover, unless those parts are already pretty fancy to begin with?