@gregeganSF@QuantaMagazine Hmm, there’s something basic I don’t understand about the overall setup, since given a welded tree you could construct an alternate graph where the second half is duplicated an exponential number of times with the label of the path midpoint attached.
Ah, but maybe then the result just says you can’t find a path to one of the exponentially many exits of that graph without forgetting the exit, which is plausible enough.