For the most part the road between Lhasa and Kathmandu is quite safe, easy, and not too unsafe. The portion between Nyalam and Khasa (from where the pictures are posted) does have a few steep drops... but nothing compared to, for example the road from Tulsipur to Sallyan (that one has claimed busloads of people). That one does appear to come close to the one from Bolivia pictured in that site...