  Near a magic twist angle, the lowest energy conduction and valence bands of
bilayer graphene moir\'e superlattices become extremely narrow. The band
dispersion that remains is sensitive to the moir\'e's strain pattern, nonlocal
tunneling between layers, and filling-factor dependent Hartree and exchange
band renormalizations. In this article we analyze the influence of these
band-structure details on the pattern of flavor-symmetry-breaking observed in
this narrow band system, and on the associated pattern of Fermi surface
reconstructions revealed by weak-field-Hall and Schubnikov-de Haas
magneto-transport measurements.
