[ffooky]

I don't know if MovieGate can accept VOBs straight but I'm pretty sure you could have had MPEG Streamclip convert the VOB to MPEG rather than demuxing it. I've had badly authored DVDs in the past and the MPEGs I've extracted from the dodgy VOB files in order to reauthor have always been differently sized which I've put down to some kind of difference in their headers. The difference in bitrate seems to me to more of a concern. Maybe the timecode breaks have a bearing here ?

Ask the boffins at videohelp ?