Currently, rollbacks are never rolled into the previous revision.
I propose a simple change making the rollback-link more useful:
If the rollback is to the pre-edit revision, and an ordinary edit would be rolled into the previous revision, just pretend it was one.
(The resulting empty revision has the summary [Edit removed during grace period]
.)
That avoids recording any more evidence than necessary of the brain-fart which led to the edit, reducing embarrassment and avoiding puzzlement to readers by de-cluttering the revision-history.
Also, reverting all changes does not retract the notification (tested with Mogsdad), thus a second proposal:
If the edit-notification was not yet signalled to the user, squash it. After all, there's nothing to see.