As an admin, have an option at the top of a dashboard to be able to view it as another specific user. For example, if user John Smith is set under the data security on a cube to only have access to...
Yes! The alternative is to create a secondary account for yourself and give it the same permissions as the person you're trying to test -- but this is cumbersome. A "view as" feature for admins would be so much more productive for testing/support purposes.