The severe difficulties in attempting a rigorous reconstruction of Proto-Tibeto-Burman on this basis [of scant data] have not prevented certain hardy souls from leaping to ever more far-flung comparisons (particularly of Tibetan or Burmese with Old Chinese, or even with Thai) in an attempt to say something about the great Sino-Tibetan proto-language. There are no doubt those who would have tried to reconstruct Proto-Indo-European simply on the testimony of Provençal, Avestan, and Old Norse. We are only now becoming more realistic. It seems wiser to concentrate for the time being on reconstructing PTB sub-group by sub-group...
linguist