It is not what WE are posting about.
And even though you say that is what you have been posting about, you HAVE repeatedly confused the terms biwire, passive biamp, 'passive' (aka fool's) biamp, and active biamp throughout this thread.
Please, take a minute to step back and see the difference between all those as they might apply to pro audio versus home audio situations. Particularly the difference between what is diagrammed in the first drawing of passive biamping versus the 'passive' biamping that is afforded by AVRs and the 'passive' biamping that WE are discussing. They are very different. When you understand the difference, you will see the confusion.
'Passive' biamping around here refers to utilizing separate amps to drive the individual sections of a speaker's passive crossover. NOT what is diagrammed here:
OK? This is NOT what WE are talking about when we talk about 'passive' biamping (or even passive biamping, for that matter). I think you understand all this. Let's not bicker just because you don't understand how WE are using the terminology.