>> I find it hard to believe that it's a rare feature.
>> The system I use (`bup`) does support that as well (every backup is
>> (more or less) a Git commit, so it doesn't distinguish full-backups from
>> incrementals), but it doesn't bother to mention it probably because it's
>> very basic.
>
> Uh-uh. Full, incremenal, and decremental backups are all completely
> different than deletion restoral.
In `bup` you basically only have full backups (but at the cost of an
incremental backup). So you never apply an incremental backup after
extracting a full backup. And hence there's never any need to do
"deletion restoral".
Stefan
