I have everything backed up on DVD's as well.
Umm..... 4 terabytes on DVDs? That's.... *calculates* .. *shocked* .. *doublechecks* ... almost one thousand (1,000) DVDs...
You, sir, either have the patience of a saint or a very patient assistant.
Well, I can see how it's not such a problem if you accumulate it over the years. But as I said, I would check that they work yearly in case they start rotting - even if I had double backups. Well, I guess if you check a DVD per day so that's a 3-year rotation which isn't that bad as long as you have two backups.
Still, a few external HDDs would be much more convenient.