Hide/Show Products/Categories in workspace rules

Summary:

I'm trying to figure out whether it's possible, via a workspace rule, to hide or show specific products or categories, depending on the logged in user or profile.

Content (required):

To better facilitate (delegate) the management of our knowledgebase content across different areas or departments on our site, I'd like to create an answer workspace rule that will restrict the values available in certain menu fields based on the logged in user's profile. I've been able to do it with certain fields, but not with product/category (it's all greyed out, listed under 'Fields on this workspace).

Am I looking in the wrong place? Or is this not possible.