on the meaning of 'word sense'

   As far as I understand the goals of lexicography, the clear
   intention is that the senses be distinct.

and this is, indeed, a laudable goal.

   Whenever I've had this problem interpreting between senses in a
   dictionary I have usually found that the dictionary's text was at
   fault, not the intended disjointness. I usually can resolve such
   problems by consulting an unabridged dictionary in which there is
   sufficient space to make the distinctions left out of the abridged
   versions--and where the indispensible example sentences are given.

but certainty on the part of the subject is not a reasonable indicator
of accuracy or reproducibility.

the fact is that most humans have very great difficulty performing
sense disambiguation.  doesn't this seriously bring into whether the
task is pertinent to language processing?