"Broadening" The Site?

I notice that the Prog Archives site is about to add a number of new "faces," among them Bill Bruford's Earthworks.  The site already includes Bruford's solo career, as well as Brand X (mostly due to Collins' presence).

But do these artists actually belong on a progressive "rock" site?  (Indeed, does Mahavishnu Orchestra?)  That is, does simply having been in a "prog rock" group thereby qualify an artist to appear on this site - even if their solo or other work is not actually "prog rock?"

It is true that the site is called "Prog Archives," not "Prog Rock Archives."  However, the "definitions" provided by the site are for prog rock, not prog jazz, and the "sub-genres" are all prog rock genres.

Some questions, then:

1.  Where exactly are the dividing lines between "prog rock," "rock-jazz fusion," and "prog jazz?"  Can these lines even be drawn?

2.  Do all three of those categories belong on this site?

3.  If they do, does this open a "can of worms" with respect to the many, many groups who are not represented here?  For example, there is a discussion thread on whether John Zorn is prog rock.  Some of what he does may be qualified as such, but not enough (overall) to place him in a "rock" category.  However, if "rock-jazz fusion" and "prog jazz" are included on the site, then Zorn would certainly qualify (as would Fred Frith et al).

4.  If it does open a "can of worms," is this necessarily a problem, or should the site be expanded to include those other categories and the artists representing them?

All comments and discussion are welcomed.

Peace.