Playing guitar is one of those skills where there is no special secret, no key to your own greatness. It pretty much takes a combination of practice, and just feeling the music.
Psychedelic rocker, and favorite of rock snobs the world-over, Captain Beefheart rattled off his “10 Commandments of Guitar Playing.” One of his commandments really hit home for me because it took me so long to realize, and I continue to struggle with it:
5. If you’re guilty of thinking, you’re out
If your brain is part of the process, you’re missing it. You should play like a drowning man, struggling to reach shore. If you can trap that feeling, then you have something that is fur bearing.
It takes a lot for me to switch off my brain and just feel, but I’m starting to do it.
I find it easier to stop thinking when I play with other people, and/or jam on the same song for a long time. Grateful Dead tunes are amazing for this.
On a much lighter note, I also liked the Captain’s 10th commandment:
10. You gotta have a hood for your engine
Keep that hat on. A hat is a pressure cooker. If you have a roof on your house, the hot air can’t escape. Even a lima bean has to have a piece of wet paper around it to make it grow.
I think it’s time to pick up the guitar for a while before bed.
(Beefheart.com Via BoingBoing)
The Geek Whisperer 
Great new WP theme D.
Your post reminds me when a guitar student asked me how and when should a band know when to stop a jam. My reply: if your band can’t do that, you can’t play as a band. You don’t jibe as a band or all of you lack ability. A band whether amateur or pro has one mind.
There was one time when I played ‘Hotel California’ impromptu and we got it perfect the first time without practice. We did it because there was no ‘ego’ involved. I even played bass guitar instead of lead just so we could jam (happens many times).
A few months ago was the first time I experienced “locking in” with another musician. It’s such a unique and incredible feeling.
I know what you mean. And if you practice just before bedtime, you’re sure to achieve something again. Keep on rockin D.