hm, but what if i have women t-shirts too? 

So for a hierarchy Category -> Women -> T-Shirts.
Slug = "t-shirts"
Permalink = "category/women/t-shirts"

that sounds like a problem. should the slug not be men-t-shirts rather? so everything up to the category, but with `-` instead of `/`? and permalink can be category/...

from a phpcr perspective its unlucky that the taxonomy insists on having a dummy root taxon that as i understand has no significance. in phpcr you can nest mixed documents, so the taxonomy could directly contain a collection of taxons. with the need for a root taxon, i will have to filter that out when building the slug/permalink.
do you use the root taxon in your logic elsewhere, is it useful? or could it be an implementation detail of the orm tree and taxonomy directly return the first level of real taxons? its not a blocker for phpcr anyways, but wanted to ask before i hack around the issue.