About the crossover, yes, resistance changes the load and so it alters the transfer function. The crossover point and damping (Q) are affected. in fact, that's precisely what we want, in the case of the π crossover, we want the components R1/R2/C1 to alter the response of the base filter. We needed to create top-octave compensation that is the conjugate of the driver's power response. To do that requires 6dB/octave augmentaton after an initial shelf of flat response. We also need about 10dB padding. And it just so happens that these things shift the base filters enough that they sum nicely given the baffle spacing of the drivers. All these things are needed of the crossover, otherwise, it would not work for our purpose.