Determine when and/or how to display summaries for vertical tabs and details ui components

In the work done to improve the layout and usability of the node add/edit page, there was a great discussion of whether or not to remove the summaries attached to vertical tabs and collapsibles (details) on this page. As currently implemented, the node add/edit page simply hides these with css (display: none), but more discussion is needed on whether to retain them and how, both for this page and for the admin UI as a whole.

A screenshot for comparison with D7 on the left and D8 (as of Feb 17, 2013) on the right (click for full size).

Considerations include:

• We need a roundup of usability data on the user experience advantages/disadvantages. This data exists, we simply need to collect it from past user studies, including the testing done for the new node add/edit form.
• If retained, how to make these summaries work for mobile and additional space constraints.