The Magic of D A D G A D
The experience of playing guitar in D A D G A D tuning for the first time is like magic. Simply tuning the first, second, and sixth strings down by one whole step transforms the fingerboard into a landscape of unexplored possibilities where most previously learned left-hand patterns no longer apply, yet every exploration leads to something new and interesting. The magic happens immediately upon strumming the open strings. The root/fifth relationship between the open D's and A's is comfortable and easily recognizable, while the addition of the open G string in the midst of all of this comfort creates a beautiful suspension.
By pressing down only the G string on the second fret, the suspension is resolved to create a D chord with no third. Pressing down the fifth string at the second fret creates a beautiful variation of G major with a suspended second (A) on the second string. Another simple move of the finger to the fourth string on the second fret creates a version of A7 (V) with a suspended fourth (D) on the first strings and again no third. So, with only one finger, the three most commonly used chords in the key of D can be played in a new and instantly pleasing way.
Excerpted from Acoustic Guitar Magazine's Best Private Lessons