I don't think it's wise for specs to include extensive justification of
decisions: WGs should be prepared to justify their decisions, but that doesn't
mean the justification should be included in the spec itself.

The justification for allowing users to suppress the automatic creation of META
elements is that during 5 years of experience with XSLT 1.0 many users have
found a need for this facility. There are a number of possible reasons: they
want to create the META element themselves, or it is copied automatically from a
source document, or the transformation is one step in a pipeline and the output
is not a finished HTML document, but only an intermediate result.

It's worth pointing out that this is the only case where serializers change the
content of the result tree. In all other cases, it's the user's responsibility
to create the required elements and attributes that will appear in the
serialized result. It's therefore hardly surprising that some users prefer to
control this aspect of the result tree themselves, rather than leaving it to the
system. 

Michael Kay (personal response)

consensus of the i18n-core-wg, telecon 27 may 2005: closed.