We had a somewhat unplanned, quick, cold but still pleasant trip here in January 2016.
Having driven around town trying to find the central palace and missing it a few times, we eventually found a space right in the centre of town. Putting on as many layers as possible we ventured out and were surprised that the palace was architecturally more interesting than we had anticipated, and the frozen moat certainly looked nice in the clear winter sun. Not really being in the mood to explore the interior we instead made a beeline for the Polish border. A swift trip over the River Neisse led to a game of scissors, paper, stone to see who would take off their gloves for a commemorative photo of our international stroll. Two minutes later my gloves were back on and we were heading for a cafe to warm up.
That really was the extent of our visit. It was fun but we were only paying lip service to it being a site of Outstanding Universal Value. Whilst it may well be the least substantial WHS visit I've ever had it probably also qualifies as the coldest.