It not what's important to me personally as a DBA or developer, but what's important to the business: users, clients, and management. Technically speaking, a partial restore that's still functional is not even an option unless the database is partitioned in such a way that supports it. For example, if your data is partitioned across seperate file groups, where all of the critical operational data is contained sperately from historical or non-essential reference data, then you can present the option to business with a high degree of confidence that it will actually work as expected. You don't want to end up spinning you wheels and losing valuable time that could be better spent completing a full recovery. These are good questions, and it would be worthwhile to plan ahead and think about what data would be needed to support a minimal degree of application functionality, test the theory on a QA or staging server, and then have an alternate disaster revocery plan documented.