Closure Rule rdf2 generates infinite set of triples

I noticed that closure rule rdf2 in

  http://www.w3.org/2001/sw/RDFCore/TR/WD-rdf-mt-20030117/#rdf_entail

will generate an infinite number of triples from any triple with an xml
literal as its object.

I was wondering if there was a reason to prefer the form of the closure
rule given over one of the form:

sss1 ppp1 xml1
sss2 ppp2 xml2

|=

sss1 ppp1 _:x
sss2 ppp2 _:x

where xml1 and xml2 denote the same XML literal value.

Brian