I'd like to know the percentage of the time over the last 70 years (when historical upper atmospheric maps started) in Dec that a two contour low didn't produce sig snow in the SE. I don't have the time to research that and it would be very time consuming. But if someone had an enormous amount of time, they could look at the daily wx maps for every Dec day back 70 years, find the days with the two contour lows, and then looked at the daily wx conditions for key cities nearby. Or if they didn't have that much time, maybe they could look back, say, only 25 years or whatever.
I do already know that the number of major snows at ATL from a pure upper low without an accompanying Gulf low moving well to the south is very low with 3/1/2009 being one of the very few exceptions. Almost all major ATL snows were associated with Gulf surface lows, often weak, whether or not there was an accompanying closed upper low. 3/1993 was a very rare very strong Gulf low, by far the strongest on record to produce major ATl snow.