GetItemFromSession vs. using the DB for importing

Topics: Customizing Orchard
Aug 22, 2013 at 9:52 PM
I'm looking at implementing the Importing method in my ContentPartDrivers for my module. In my case, I my ContentPart references other content items. In some cases, these items will be users, while in others, they're be a custom content type of mine.

Generally, I understand that I should use GetItemFromSession to get a reference to these ContentItems. This makes perfect sense to me. The CommonPartDriver in Orchard.Core does this differently though. In that case, the user is retrieved via the membership service. This seems to indicate there are time when I SHOULDN'T use GetItemFromSession for importing. Is that correct and if so, in what cases should GetItemFromSession not be used for importing?