How does everybody here 'let go' when they're playing guitar?

What I mean is when you just let rip or get into the zone or whatever but the main thing is you're not thinking "where are my fingers going?" or "what's the chord progression here?".

I know how they did it in the old days but we're all supposed to be so much better at 'finding alternatives' these days!

I was just listening to Planet Rock Radio, here in the UK, you see and I got to wondering :)