Interesting issues. No real arguments against your points but I've chosen to go the high pass route in my three AVR-less systems...not that it is as necessary but I see it as desirable. So powered JBL subs in the listening room have a built-in high pass, and in the less critical tv room and bedroom I use Crown amps which have adjustable low and high pass filters. As for DSP I again take the view it's better using than not so I have PW-Link Anthem RC in all three systems. Bedroom and den I'm typically in the same listening position. Listening room is trickier but still believe that employing room correction for bass for one listening position is better than none at all and the PW-Link streamers are cheap. Summed mono with two subs in the listening room and den. Stereo sub cabling would be less messy for sure.