Well, the audience rarely misses anything, as it seldom even notices anything (at least, consciously)! But perhaps it is I that is the idiot here...

Because I DO use stereo, and miss it when I don't have it, and my audiences, especially when I've played a mono venue and they hear me doing stereo, often come up and go 'you sound so much better here...'

I just smile and thank them.

What do they know, anyway?