JoJoe,
I agree with Arif. The soil looks a little moist and kind of packed. The stems are also long and are bending over and touching the soil again. If you look at your summer picture, all the stems are straight up with tight clusters and not bending over where the leaves touch the soil and can rot or get knocked off. Not sure why the stems are breaking near soil line; could be the moisture issue.
If you are bringing in a new pot, make sure you carry on with the adding of rocks into the new soil to improve drainage.
If you are willing to cut, then cut where you want new clusters to form. I would think you wouldn't want clusters starting at the top. Think about cutting rooted stems halfway down. I would then just strip the leaves off the loose cut stems and start the leaf propagation in another pot. I usually don't deal with the cut off stems unless you have had better luck with rooting stems.. Also try not to have too many plants (stems) in one pot because it tends to have the clusters bump into one another and knock off leaves. Hope this helps, JoJoe...
(Valentine Day)
The elongation of stems I think is probably a light issue but i am not familiar with keeping enough lite using grow lamps. I am more of a find-the-sunny spot and put plant there even if it is on the floor. This approach requires you to note the sunny spots thruout the day in your house.
