Some research shows that the following restrictions are enforced:
- To delete pages, the 'delete' right is required (that's logical)
- To view deleted revision metadata (timestamps, comments, users), the 'deletedhistory' right is required (also makes sense)
- To view deleted revision *content*, the 'delete' right is required (?!?)
- To restore deleted revisions, the 'delete' right is also required (also wacky).
IMO, the following should happen:
- A separate 'undelete' right should be created
- Viewing deleted revisions, *including content*, should be possible with the 'deletedhistory' right
- Restoring them should be possible with the 'undelete' right
One could argue that being able to view deleted revision content is just a copy+paste away from being able to restore them. Alternatively, 'deletedhistory' and 'undelete' could be merged.
Either way, the situation as it is now (undeletion requiring the 'delete' right) doesn't make sense.