Ok Dorothy, and just so that Ralph knows what you're talking about, here's where I'm coming from.

Rigid tempo - tempo giusto, is neutral - it has no intrinsic musical worth. You could argue that it implies stability, but that stability needs a period of instability to contextualise it otherwise it's a musical nothing.

Most musicians use some modulation of tempo as a musical device - the possibilities are many, and I'm not going to bore you with examples - I'm sure that if your listening includes genres beyond pop you can find your own.

Personally, I'm more than happy to play to clicks, but I don't feel it's appropriate to bh - glad to say that the few times I've tried it in rehearsal I've been politely asked to desist as it was making the whole thing overly sterile.