I just did a similar job on a cermark banchee which is a similar type of plane with a tail set up the same as that. A mate of mine has one also and though the tail has stood the test of time I swear you can feel the flex in it in flight. As I needed some weight in the tail anyway as I have a Saito 82 up front I decided to cut out the joiner and fit separate servos for each elevator in the tail, why put weight on if it's not going to work for a living I'll tell you if it makes a difference tomorrow if the weather is good to us I should get to maiden her