There are two parts to this. The second lesson is a variation. The dominant chord in this 2 5 1 is altered.
This creates a nice way to create flow with the fingering when alternate picking in the style of John Mclaughlin. As you play through the Notation/Tab [below] this will become apparent very quickly.
John Mclaughlin guitar lesson finishing with a D flat Triad for G7 alt
LINE BREAKDOWN: Breaking down the line into 4 note cells [Tetrachords]
VARIATION of the John Mclaughlin jazz fusion improvisation guitar lesson finishing with an E flat Triad for the G7 alt
For more info John Mclaughlin has a DVD: