OBG, I think it depends on what your crossovers look like inside the speaker. I'm assuming you have 4 binding posts on the back of your speaker.... 2 for high pass and 2 for low pass, and they're normally strapped together.
If I were to design such a speaker, I'd have two separate crossover networks then, one per pair of binding posts. Each would be a passive crossover... I don't know that removing them would be a good idea in your bi-amp senario though, because that may throw the impedance seen by the amplifier all out of whack? (i.e. the crossover adds some amount to the speaker impedance)
Am I reading the article and your post correctly?