Wow Chris, you spend a lot of time quoting 
Naim stereo does excellent stereo with the speakers flat against the wall so that kind of fcuks up the Technical paper some geezer wrote in the 40s.
Chris, I may well not have been to as many concerts as yourself. However the only concert I attended that gave any sense of depth (as opposed to a wall of sound) was Pink Floyd. They were only able to provide depth because they had a six (as I could count anyway) speaker set up around the hall.
The fact I can point out where the drums are coming from does not to me indicate depth of sound, only what my eyes are telling me.
And once more for clarity. A speaker cannot fire out the sound of a guitar and have it stop one metre in the room, I refer you back to the pathetic comment earlier in the thread about how someone was able to walk amongst the soundstage.
Not possible with two speakers.