How does the Margin (grow/shrink) effect handle anisotropic voxel spacing?

Hello,

I’m using the Margin effect in Segment Editor to isotropically expand a segment on CT data with anisotropic voxel spacing. When I request a 3.00 mm margin, the UI reports an actual expansion of 2.9 × 2.9 × 2.5 mm, corresponding to a 3×3×1 pixel kernel.

Is this because the Margin effect uses a whole-voxel kernel, rounded per axis, rather than a continuous distance transform?