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Individual users or groups can not be used in place of one of these special purpose groups because IIS recognizes these groups and treats them differently.
Details
Some files, such as .ASMX files, require the List folder / read data privilege. Other files, such as font files, require that privilege as well as Read extended attributes and Read permissions. Overall IIS handles requests for different file types in different ways and some file types one of these three groups and the associated permissions.