go for it, reg. On top of that, tear apart a couple rhizomes. I would do it a touch closer to spring though. Check out another thread on here about how someone turned just a couple VFTS into 40 something.
I find that they are tough as nails. Last winter I took my biggest VFT, cut the rhizome in half or so. The part that had the original leaves kept going ok, just a little smaller, and the other half of the rhizome turned into a rather sizable clump.
I'd show you a pic... but I just repotted everything to it's all spread out now.