Why do you think Bi-Wiring improves the sound ?

I have always bi-wired my speakers.
The concept makes perfect sense if you consider that the voicecoil is kinda like an electric motor.
Give it power and it goes.
but an electric motor is also an electric generator if the movement is caused by an exterior force.
The driver doesn't comes to rest instantaneously after being driven by the amplifier.
momentum keeps it going and that can cause the creation of current which feeds back to the tweeter. potentially.
Bi-wiring gives this current a place to go as it is drawn to the ground of the amplifier.
Path of least resistance and all that.