Hi AM folk,
If you have the patience to really follow this video, Guthrie Trapp demonstrates how to play a harmonized lead over a I, IV, V chord progression. The caveat is, the same shapes can have different applications in the context of the different chords and you will need to know your notes on the second string really well. It helps to understand intervals, but maybe more important to see the underlying chord shape. The melody note will always be the higher note, the harmonized note will always be the lower. Also, don’t confuse how the shapes relate to the chords and how you can create the harmonized 6th C major scale on the second string.
Some of the tricks include sliding between two forms of the chord, with passing tones in between; sliding from a major form to a dominant 7 form; different ways to resolve from the V-I and IV-I (including a major-minor walkdown from the IV). He does it all on the second string set (D,G,B) but the same shapes could be used on the first string set. Admittedly, I felt overwhelmed the first time I watched this but now I see it and it’s really worthwhile.
John