  An updated study of measuring the W mass from a polarized threshold scan at
ILC is presented with an emphasis on evaluating scan strategies that control
experimental systematics. Highly longitudinally polarized beams of electrons
and positrons such as are feasible at ILC offer significant advantages in terms
of statistical power and in-situ control of background. Eventual experimental
precision of around 2 MeV can be envisaged from this technique. Further work on
both the accelerator design and theoretical uncertainties will likely be needed
to take full advantage of this opportunity.
