This video discusses the second half of the Allemanda, clearly showing how Bach has achieved the long-range arch of the piece.
A valuable discussion for performers on any instrument, musicians can take the concepts and apply them to other pieces by Bach.
We are often taught that the second half of a binary piece starts in the dominant and weaves its way back to the tonic—but not does not reach it until the end of the piece. However, in the B section of this allemanda, Bach actually moves back to the tonic almost immediately, then to his pivotal key area, and then again back to the tonic for a final close.
The video also discusses the French style versus the Italian style, and how they are both interwoven into the fabric of this dance.
Be sure to view PART-THREE first, as it discusses the first half of the Allemanda, BWV 1002. Parts one and two will also be invaluable in setting the stage and looking at the historical context in which Bach wrote this music.