Aaaah right, nouns comprenons! Yes, the mechanical working through of sterile variations, each minute dot and twiddle of difference being presented as a whole part in itself, is to me anathema, it's the kind of exercise that music teachers would give their pupils in the 18th century, it's why I'm not fond of Salieri and Quantz.

On the other hand, the SAME variations, dropped casually and sensitively into a session (or performance if you like that sort of thing) can add extra dimensions to what otherwise could become the mechanical repetition of a tune, pick one that harmonises well with what everyone else is doing.

It's all a matter of presentation and timing. And yes, I do often practice variations to drop in, I'm not good enough to do it spontaneously very often.