Personally I've been impressed over the years with how LITTLE stress the wing joint has in a properly designed plane. My mid wing planes (60 size Edge 540, self-designed aerobat, and a 30% Yak-54) are held in either by rubber bands or nylon bolts. One day as I was cleaning up, I was taking the wing off my Edge 540. There was only one loop of rubber band holding the wing in place. If you watch the video of Mac Hodges B-29 crash, look at how many spins it takes before the wing finally slides out far enough to come off.

5 minute epoxy has more than enough strength to hold the wing halves together. Heck, I bet packing tape would work.

Brad