To MTed & Melissa-
Yikes, my post way upthread must have sounded a lot more elitist or something than I meant it.

My point was, partly, exactly what MT and others have said (better), which is that theory is just observation of practice. Learning many songs to which one hasn't had to work out the chords, one can't help but make observations whether one cares to systematize that knowledge into "theory" or not.

And Melissa, you are right, I could have left off the "better" value judgment - but I personally find that way to result in better understanding when I am teaching.

I didn't mean to imply that there is anything illicit or presumptuous about trying to "work out" chords without some knowledge of how they function (whether arrived at by book-larnin' or observation) but that I have found it to not be a *fruitful* effort most of the time. Meaning that one's effort is better spent gaining some understanding before trying to reinvent the wheel. (Don F made this point somewhere upthread, too.) The vast, vast majority of songs fall within a reasonably small range of common practice, and one does learn to identify the "likely suspects" out of all the possible chords rather quickly.

Having said all that, I have at times (despite my obviously encyclopedic knowledge of theory) resorted to plucking at all the possible triads containing a given note before I arrived at the one that sounded right.

And I, too, began my epic explorations of music theory with a bent-up cardboard Mel Bay circular slide rule thingy found in a used guitar case. Small world, eh?

Cheers
-Glenn