Question here. I understand the basic concept of the CAGED system. What throws me off, however, is that the "D" chord shape is really just a simplified form of the "C" shape moved up two frets. I guess we need the "D" shape in the sequence to maintain the flow up the fretboard, but that is a stumbling block for me.
Another question: The five scale patterns you listed in another thread are based on the same sequence of CAGED chords, right? I think I'm starting to see the sense of all this.