Just a little niggle, but I want to lay concerns to rest. How strong is the above mentioned setup when used in the spin/fly setup? I think that when casting and fighting fish it experiences some bending stress at the joint.

Also, I know it would look a little odd, but can I still use it with a downlocking seat configuration (Fuji skeleton, wood ergo-insert)?. Would I have to recess the fighting butt attachment inside the wood insert?

Obviously, the longer the rear piece behind the seat and the larger the fish (and heavier the line) the more stress you'll have on that joint. Most builders don't seem to be having problems when the length of the rear piece stays within reason and the quarry falls short of very large and powerful fish. This is something you'll just have to use some common sense on. If in doubt, test your seat and extension against the heaviest load you expect for the line size you'll be using.

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