Well, not absolutely sure what does a IFOedit's mock strip, but, I believe it does:
A) IFO Tables adjustment (the exact table depends if it is a VOB extras or menu extras strip, and in the last case if it is a VTS or a VMGM one)
- Vxxx_C_ADT reconstruction
- Vxxx_VOBU_ADMAP reconstruction
- Vxxx_PGCI_UT / Vxx_PGCI. I believe only the cell attributes (like sectors and so on)
In the first pass reading the VOBs, IFOedit gets all the required info for the adjustment of these tables.
B) VOB modifications
B.1) Pointers adjustments: This is the more complicated part
In
http://dvd.sourceforge.net/dvdinfo/dsi_pkt.html you can see the structure of the DSI part in a Nav pack. The most of these bytes/pointers are recalculated. There are some options in VOB experts part of Vob Extras dialog to select "groups" of pointers to be adjusted.
B.2) PUOPs / Macrovision removing
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When do you need to do a mock strip?
In general, it is a safe way to reconstruct the DVD pointer structure (as I pointed out, there are thousands of them), and should be the first thing to be done in the case of VOB manipulations.
In the past, the methods for blanking/replacing cells are basically to replace the cells in a brute way inside the VOB. The resulting DVD was not playable, but after a mock strip, all the pointers are readjusted and the DVD plays again.
jsoto