You can do this with any NAS. It does not make it a DAS. You don't even need to use iSCSI to do it either.
At the end of they it doesn't matter. The end results are the same. For those who take a lot of extra measures to ensure redundancy like I do, DAS or not....whatever....Files from point A to point B.
As for iSCSI, I already know that. So what's your point? Can you not achieve the same functionality with a DAS as with a NAS?