Interesting.. when reading that you can restore a single filegroup, I wondered about the wizdom of doing a filegroup restore rather than the entire database because of potential referencial issues. (This book was lacking because it often described what you can do with no examples of scenarios when or why you would want to do them).

But if the data is partitioned so that you don't have two-way dependency between tables in different filegroups, then this wouldn't be an issue. For example, if you had 2001-2005 sales data in one filegroup and 2006-2010 sales data on another, you could restore one without needing to restore the other. Or if you did need to restore both and they were on different I/O paths, you could restore them simultaniously in less time than it would take if they were in one larger filegroup. Am I understanding this right?