Don't let mergemaster beat you down [was Re: Failed update]

[Arthur Chance]

Wayne Sierke wrote:
> I lost practically all of my 'mergemaster pain' when I adopted the habit
> of using it with -iUP options:
> 
>         -i	Automatically install any files that do not exist in the des-
>                 tination directory.
>         -P	Preserve files that you replace in
>                 /var/tmp/mergemaster/preserved-files-<date>, or another
>                 directory you specify in your mergemaster rc file.
>         -U	Attempt to auto upgrade files that have not been user modi-
>                 fied.

How does -U compare to -F? I've found that saves a lot of tedium.