When I bought my boat the tiller was split right through the mountin holes al the way up the the end, basically in two pieces.
Previous owner's attempted repair with gorilla glue didn't work.
So I used thickened epoxy and lots fo camps. Followed with some cleaning, sanding and many coats of spray spar urethane.
Here's the result, not perfect but much better:
(http://www.buildboats.com/cp16tiller.jpg)
(http://www.buildboats.com/cp16tiller2.jpg)
that looks pretty good, have fun!!