FYI I’ve been listening to my system for a couple of weeks after vertically bi-amping rather than horizontal bi-amping. There is defiantly more punch and immediacy! My wife commented on it. :)
Yes, it's easy to understand, bass/upper bass is the most "power sapping" area from an amp in music.
In vertical bi-amping the whole power supply of one amp, is dedicated to just one bass driver instead of two, like in normal stereo or in horizontal bi-amping.
And forget about bridging, it just turns "good" amps into higher wattage "average" amps.
Cheers George