While the standard minor pentatonic scale includes these 5 notes....root - 3b - 4 - 5 - 7b .......the blues scale includes one more note -- the augmented 4, which is a semi-tone ( half-step) above the 4-note. It is also known as the blue note. This gives a total of six notes, which is easier to fit into a blues shuffle than the 5-note pentatonic scale.
We practiced using riff #1, with the 6-note blues scale tacked onto it in a 12-bar blues progression. I've tried it with the blues scale going forward and backwards and it sounds good either way.
