  We discuss the relationship between the graphical amplitudes T, C, P, ...
used to parameterize nonleptonic B decay amplitudes, and matrix elements of
operators in the soft-collinear effective theory (SCET) at leading order in
\Lambda/m_b. Using the SU(3) flavor symmetry of the weak Hamiltonian we derive
all-order constraints on the electroweak penguin contributions to the Wilson
coefficients of SCET operators.
