I've been aware for some time now that there has been dissatisfaction
with the concluding portion of Adventures of Huckleberry Finn, but not
until this last year have I become aware of what seems to be a sense of
failure in much of his work.  

A few weeks back I mentioned I was reading Cox's Mark Twain The Fate of
Humor and I was surprised at the thought that Connecticut Yankee and/or
The Prince and the Pauper were failures.  Upon finishing this book it
seems to me that Cox felt most of Twains work were failures.  And this
surprised me greatly especially sense he seems to be so well informed on
the topic.  

I started today on Lawrence Howe's Mark Twain and the Novel.  This
appears to argue that the failures were not Twain's but are structural.
Nevertheless, the idea that there are failures or faults in these works
surprises me.  In fact it disturbs me.  I suppose this is because I am
not a literary critic  or even academically trained in English (my
degrees are in Geography).  In my mind, a book, in this case a novel, is
a failure only if it fails to interest the reader and/or proves to be
unreadable.  This is not the case with any of Twain's works in my
experience. 

On further searching for why this sense of failure exists I came upon a
review of Cox's book by Kristin Brown.  It would seem that Mark Twain IS
a Humorist and must write humorous material, otherwise "Twain had
attempted to suppress his genius".  This is the crux of my problem with
the idea that there are failures.

This strikes me very much like the argument that Miles Davis was a
failure after he progressed beyond Bebop.  An artist is not allowed to
venture away from their established genre.  Humor might have been his
"strongest suit" but by no means need it be his only suit.

Thoughts?