After ten years working at a hobby shop and seeing the wreckage, I do. But for every wrecked plane, I realize there are 20 others that are flying. I don't overdue it and don't add too much weight. I just try and bond the wing skins at the joint. Most of the forces in the wings we fly are actually in the wing sheeting for the most part. If the sheets are poorly bonded and come apart (the butt joint used commonly is not always the strongest), all of that force is funnelled into that little connector. I wouldn't trust that little connector with my life, or in this case my money. If the connector is made out of a strong material, the wing will break around the joiner. I saw a bunch of failures were the wing broke around the joint. I have also seen those ARTF trainers with the metal rod wing joiner having pulled through one of the panels. If a wing has a real strong reinforced joint, it will fail to the side of the joint. So you can over do it and add a lot of weight.

Is it always needed? No. Is a wing failure common? No. Could a certain plane benefit from it? Who knows until the wing has broken or the model is worn out and retired. Will I always glass my wings? Yes.

Are all joints designed to be strong? Yes. Are all designed never to fail under all circumstances? No, it would be far too expensive.

I just see every model an investment and take the extra time to reinforce it. But I think one should do as he feels. I do have to admit that I do have one plane without a glassed joint. It is a 30 size Cub with a Saito 30 on it.