I'd imagine most aluminium and carbon rims and most tires are pretty dang easy to get through with a hack saw. But for the OP's pee/snack breaks the Sheldon method should work fine. I'd go the extra mile and include the seat tube like you did on your Trek there. I reckon the Kuwa's rear triangle's too big to do that on.

If the thief is carrying a cutting tool that can get through U-Locks and they come across a bike with a really nice frame and have a getaway vehicle they may just decide to rip through the rear wheel to get a Sheldon locked bike free.