Users are U-M are finding that the updated Share screen is confusing and slow, now that it contains roles from all sites to which the user belongs. When sharing a portfolio within a given site, they have the expectation of roles just being shorthand for selecting individuals within the site. The option for direct user sharing is sufficient for the rare cross-context needs.
We would like to have a configuration option such that only the containing site's roles would be shown for portfolios completed in a course/project site. Portfolios completed within My Workspace may require a different model entirely and should be considered separately.