You should probably mention somewhere in the body of this hint that the list generated by the second terminal command is not complete. The 2005 hint you mention in your first paragraph explains, largely in the comments (especially this one, this one, and this one) that there are at least a couple of other mechanisms used by Time Machine to determine which files and folders will not get backed up.

Also, your last paragraph seems to indicate that the list returned by mdfind will include items that the user has manually excluded using the Time Machine "Options..." panel (in its system preference pane), but this doesn't appear to be the case (and is directly contradicted by the 2005 hint, by the way).

I've corrected that, thanks.