[Xapian-discuss] Stem doesn't remove ' from end of words that are possessive?

[Jarrod Roberson]

If I stem a word with  " 's " at the end it strips off the s and leaves the
' hanging.
this means that possessives don't stem down to a useful term.
Removing the " ' " as well as the trailing " s " would be a more useful
behavior.

For example:
    uncle's stems down to uncle'
if it stemmed down to just " uncle " that would be a much more useful
behavior I would believe.

Is this the intended behavior? If so why?