In August, I received some figs in the mail, immediately repotting them. Then, 9 days later I decided to plant a few of them. When I took them out of the (larger) pots, I noticed that the roots had already expanded all the way to the edge, all in just 9 days. It held the soil together when I planted them out.
Pic here:
I’m not sure if the root growth would be as fast over the winter, but from npolaske’s post, it sounds like it wouldn’t hurt to try.