@knotscott makes a very important point: electronic crossovers provide only "textbook" filters. TF’s are 1st/2nd/3rd/or 4th order, which create slopes of 6/12/18/or 24dB an octave for each driver. The internal passive crossovers in almost all good loudspeakers do more than provide just those slopes; they also contain parts that create compensation filters for the drivers themselves.
To best bi-amp a loudspeaker, the speaker should really be designed with that as a given. Older Maggies (those with parallel crossovers) are perfect candidates for bi-amping, as their crossovers contain no driver compensation networks, only textbook slope filters. The .7 series Maggies contain not parallel but series crossovers, so need to be modified to allow bi-amping.