  The maximum magnetic moment to angular momentum conjecture, recently posed by
Barrow \& Gibbons, is in tension with the generally accepted parameters of
magnetars. According to the conjecture the dimensionless
Schuster-Wilson-Blacket number, $c\mu/J\sqrt{G}$ where $\mu$ is the magnetic
moment and $J$ is the angular momentum, should be of order unity. A resolution
is to assume that not only the low-magnetic field magnetars, but all magnetars
have their super-critical fields in the higher multipoles. This requires the
presence of external torques other than the magnetic dipole torque, such as
from fallback disks or winds, on these systems to yield the measured high
spin-down rates.
