I didn't close my pool this winter. I still run my pump daily and ensure that it runs anytime the temp approaches freezing. At first, I was still testing regularly and adjusting my pump's run time depending on the conditions.
I've found maintain the pool in the winter can be a real pain, especially to my hands my water is getting really cold. So, I've become really lazy. I pretty much just run the pump from late evening until late morning which is almost always covers the hours when the weather approaches freezing. If we get a really cold spat, I'll run it 24/7 until it passes. Also, started adding 1 jug of bleach a week. Its easy to remember and easy to explain to my wife if I can't get to it. But even at that rate, my FC has been climbing (I still test the water). I don't mind so much, since it provides a little insurance and allows me to skip a dose from time to time.
If I was less cold adverse (lol, read lazy) I'm sure I could get away with running the pump much less and adding less bleach each week.