Metadata for all and PS for metadata (Was Re: where to hang the metadata?)

Sandro Hawke wrote:
> 
> So the proposed compromise (which Chris also sent the list - we talked
> about it on the phone with Christian) is to have both the <Group> and
> <Rule> wrappers.  I'd also like metadata everywhere else, too, but I
> think I can life with this compromise if everyone else can.

Just for clarification: what would be the argument against allowing 
metadata on all objects, that is, allowing a <meta> role element as a 
child of any class (capitalized tag) element (this question is othogonal 
to that of identifying rules vs groups)?

Also, since there is a consensus that metadata do not impact the 
semantics, why do we need a presentation syntax for the metadata?

More precisely: there seem to be a consensus that metadata about rule 
groups and individual groups still need have a presentation syntax. Does 
that indicate that some metadata about them should be part of the BLD 
dialect (e.g. group/rule name/IRI etc)?

And, of course, having a PS for the metadata on some Groups and Rules 
does not imply that we need one for metadata on other classes, even if 
we agree to allow metadata on any object; not for BLD, at least. Or does it?

Cheers,

Christian