Teardrops n Tiny Travel Trailers

I am doing some youtube research on a foamie camper that I want to start to build come the new year. I see a lot of people who use foam to build their camper cut notches into the foam boards and fit them together like puzzle pieces, supposedly because it creates a stronger joint. But I thought that the glue creates a stronger bond then the foam itself, so it wouldn't matter if it's notched or not. It essentially becomes one piece and if it failed, it would fail where the foam is weakest, whether notched or not. Is this true? what's the consensus?

Notching provides n ore surfaces for glueing parts together

Notching helps align the parts as you put them together. But so does using hidden splines in grooves and is easier to do.

The foam is weak, I doubt notching is much stronger than a well done glued butt joint. It's the canvas or glass skin that provides the real strength.