Don, I agree with you... Stereo is a must... The effects are designed to be stereo.... and samples are now usually sampled in stereo..
If folks think mono is fine... they are being misguided..
Also movement of the sound from the drum kits...toms or location of cymbals in the stereo field..
Just the sound of a Rhodes sound... has to be stereo..
Horn sections and falls without stereo ..
yuck..
As for the audience not hearing the difference .... they do.. they may not know why the difference but will hear the difference..
Now I still think the design of Bose in stereo (2 units) has cancellation with overlapped sound.... and the sound suffers..
Stereo speakers still have the advantage.. If you need the best sound.. STEREO..