Securing the Cube - Expert Cube Development with SSAS Multidimensional Models - page 263

The relational data source for the security section will look like this:
Both the new dimension that contains reseller users and the new measure group
should not be made visible to end users; they cannot be used in users' queries, and
their presence might be confusing to them. However, as it's useful to be able to see
them for debugging purposes, we might be tempted to create them as visible and
then use security to deny end users access to them. Unfortunately, as we found
earlier, we can't deny access to an entire dimension using dimension security, so
setting their visibility is the only thing we can do.
Setting an object's Visible property to False to hide it from
end users is not the same thing as using security to deny access
to it. Even if an object is not visible, it can still be used in a query
and results returned for it.