The Hanger 9 trainers come with a rod and pin that insert inside the wing to keep it from twisting.
I have always just used the tape on my own hanger 9 planes, but instead of the thin strip that comes with the kit I use 2" packing tape.

I have crashed, and seen others crash their H9 planes and never seen the wing separate with the tape.

One thing to consider is that if you ever outgrow your plane and want to sell it, shipping would be nearly impossible with the wing glued together.

I use the tape and feel confident that it is enough or the MFG wouldnt recomend it.

Just my opinion