Magnetic field burial and flux freezing together distort the initial dipole and decrease the magnetic moment; however, the local field strength may increase! ZEUS says that the magnetic structures are Parker unstable but the instability is suppressed: In the end, the substrate exhibits global MHD oscillations. The interesting claim is that the end state could be a 10^15 G (!!!) magnetic field "wall" that could affect type I X-ray bursts, for example. The idea is exciting because there are severe discrepancies between observations and X-ray burst models that are difficult to explain through nuclear physics uncertainties alone, but the presence of such a structure, particularly at the ignition pressures of X-ray bursts (which are << B^2/8pi for B = 10^15 G), are difficult to believe.
A more plausible, yet no less exciting, idea is that asymmetric field burial could produce a quadrupole; the resultant gravitational radiation would limit the possible neutron star spin frequency. This could explain why all neutron stars have spin frequencies <~ 700 Hz, well below the break-up spin.
Andrew also suggested that such a wall could explain double bursts, as each hemisphere of the NS could burst separately. A point that Andrew didn't make explicitly in his talk; there exist also triple bursts, yet NSs only have 2 hemispheres. The possible solution in this paradigm is a multipolar NS and B field, with multiple disconnected accreting regions. It would be interesting to work out the observational burst implications.
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