Yes, it's because Linux Mint is already collaborating with the developer of Mate Desktop (a Gnome 2 fork) that I asked this question.
Since Mate is neither part of Ubuntu, nor part of Debian, it's seem irrelevant to me what Ubuntu or Debian would normally do. Mint is already going off in its own direction here. And since, as Clem says in the Mint blog, Mint and Mate may work together on a system that allows Gnome 2 and Gnome 3 to run on the same sytem and since the Ubuntu sources in the main edition of Mint come originally from Debian anyway, I don't see why these Gnome 2 packages couldn't potentially work in Linux Mint Debian.
No one is talking here about LMDE holding back Gnome 3 and Shell, as craig10x said. I don't see where my original post suggested that. The blog post from Clem says they're working on a way to make the two run together. So I was just wondering if this might be provided as an option for LMDE also. It would be a great option.