Doctor M said: If your DVD is less than 5% oversized, using DVD Shrink on it as a last step will have a negligible impact on quality. Any more and I’d strongly recommend stripping something or re-encoding some assets at a lower bitrate.
Oh, sorry I just realized how extremely vague I was being. I was wondering why in Part VII of your guide you recommended using DVDShrink if your final DVD (after muxing and adding menus) turned out to be a greater size than a single layer DVD. DVD Rebuilder normally yields better results in terms of video and audio quality even if the DVD being compressed is more than 5% oversized.
Anyway, it was just a suggestion, and I am admittedly not very tech savvy. In any case, thank you so much for this guide; it must have taken some time and effort to make.