D&D intelligence, not IQ. 10-12 is human average, so I'd say it's not terrible for the purposes of understanding the underlying themes of Ulysses or Finnegan's Wake.
While that is true, there has been quite the effort to make a test that can actually show the lower end of the intelligence spectrum. And no matter how or what you test, 17 IQ is in the range of severe cognitive disability, i.e. the equivalent of the knowledge and ability of a 3 year old.