Watch the Two By Two online guitar lesson by Anthony Stauffer from 50 Slow Blues Licks You MUST Know
Although B.B. King is not known for his chord work, his soloing is often augmented with two note chords. This example shows how using two note chords in place of single notes can create a rich, elegant sound, much fuller than you'd expect from such a simple lick. It's played right after the first beat of bar #11 when the progression lands back on the I chord.