(If Stephen is reading this, perhaps he might give us some examples
from the Tibetan?)
Yes, I'm here -- just a bit busy as always. Anyway, the Tibetan and the
Chinese equivalents I have seen do not favour an interpretation along the
lines of the "unique / sole way". They are closer to what Dmytro suggests,
"leading to only one place" -- in the sense of being a kind of "oneway /
unidirectional path" leading there.
PS: I have not given up on preparing another Buddhist Chinese lesson -- I
have got some notes together need a bit of spare time to tidy things up.