I friggin love boulderland!!! It's about 90kms of the best high altitude crazyness around and probably a lot of fun to backpack
The whole plateau you crossed before getting to Litang was once the ocean floor that uplifted to 4500m and then eventually got covered in glaciers. The glaciers dragged those massive boulders around and put them in all kinds of whacked out places. You were lucky to go through there with such nice weather.
In 2008 a couple from Australia went through that pass and has to spend the night in a snow storm at 4600m before reaching Litang. Snow was so deep, it was over the axles. Can you say sleeping bags and good tent???
Did you see the Rabbit Ear Mountain (TuEr Shan) on that road?
CC