Richard,

I had a similarly unpleasant failure with one of the gunwale scarf joints for my Brinck Baidarka recently. I did basically what you are thinking of, sistered on some supports with Gorilla Glue. Everything seems to be fine now.

If you would like to see the damage and repair to see how applicable to your situation it might be, try

http://www.seanet.com/~acunning/hobbies/index.html

Then click Kayak Building and Brinck Baidarka

I used 1/4 Oak on either side because it was handy and would mess with the lines too much.

Hope this helps.

Aaron Cunningham