Brian is a big proponent of the CAGED system. Essentially everything he does relates back to it. If memory serves me, those 5 positions in the blues lead course are the pentatonic scale shapes, and they each lay over a CAGED shape. The pentatonic scale is 5 notes out of the 7 in the major/minor scale. You just need to add 2 more notes to get the full scale. A great learning exercise would be to take each of the 5 positions, see where the root notes are, and then find the CAGED shape at that location. When you have the scales associated in your mind to the corresponding CAGED shape, it becomes pretty easy to play over a given chord.

Hope this helps. Ask more questions as they come up for you.

Hi Dom,
Brian teaches 5 shapes for the pentatonics and the same shapes apply for the minor and major pentatonic when you shift from minor down 3 frets to the major using the same root.
The CAGED system generally refers to major chord voices and the major pentatonic shapes fit within the CAGED shapes. Brian did a series of lessons on this idea, EP556-560.
You can create a minor version of the CAGED system (I know Brian shows this in one of his EP’s). The minor pentatonic boxes will fit within these chord voicings.
An alternative way to see this is to consider the “octave root system” (ie. the layout of a given root over the entire fret board). If you consider an “E shaped” major bar chord, there are three root notes within the major chord voicing and box 2 of the major pentatonic will sit within the shape.
If you now consider an “E shaped” minor bar chord, the E roots are in the same place and the box 1 minor pentatonic sits within that shape.
You will ultimately be able to mix the major and minor pentatonic together if you can see the major and minor box shapes around the root notes in the position you are in. Root notes are always going to be the key to navigating the fret board.
John