I thought IVTC is ONLY to remove pulldown, not to turn something that's interlaced into something progressive (unless the source was progressive). Now I don't know exactly how it is for NTSC camcorders but for PAL camcorders the camcorder while filming doesn't capture a frame and turn it into seperate fields. It's capturing fields at 50 fields per seconds. Because of this it is hard to turn interlaced camcorder footage into progressive footage (because the two fields are not shot at the same time they can differ a lot especially in faster moving scenes). But as I said I don't know how it is for NTSC camcorders.