[noggin]

And yet an IVTC would be preferred to any deinterlacing on a lot of interlaced MPEG-2 content (at least in the US).

IVTC is a form of de-interlacing isn't it? (You are taking an interlaced signal and removing the interlace)

You are taking an interlaced signal, detecting the redundant field, and de-interlacing based on the position of this redundant field (i.e. weaving the pairs of non-redundant fields and then adding a 3:2 frame cadence again in most cases, so you can cope with mixed 3:2, 2:2 and native interlaced content in the same stream?)