I'm assuming you mean this thread? I think I get it a bit, but I was hoping for something a bit more in deep. But if I got it right, and do correct me if I'm wrong, basically it's a restarting from scratch because the changes in the base DF would need be a lot of work to update what was already there and so they might as well fix some deep problems in the previous versions?
Yes.
MDF at it's current form has a very large mod with V6.2, still using the old DF version.
And the MDF Reborn, using the new DF version, but only has Dwarf, Gnome and Succubus content so far and some misc stuff... still a large mod in itself, but way smaller than the old MDF.
I'm currently travelling, only access to netbook, so no large changes planned.