I think the problem with INF conflicts is that we don't accurately replicate the way Windows copies INF files. When Windows installs a driver, it creates an INF called "oemX.inf". I suspect that we simply copy the INF with its current file name into our INF directory which can obviously lead to conflicts, especially during driver updates. Correcting our implementation of OEM INF copying will fix the problem the proper way.
"When third-party drivers are installed correctly, the .inf is renamed to Oemxx.inf (where xx is a sequential number) to make sure that there are no name conflicts with drivers that are included with the product and with other third-party drivers"
Reference: http://support.microsoft.com/kb/813449
The rest of the patch looks ok to me.
Regards, Cameron