After the issue of taste, a good sandwich must be structurally sound. It must be able to hold up under pressure. For example, the McDonald's Big Mac (yes, burgers are sandwhiches), that secret sauce is very slippery. It is placed next to the lettuce, so it is not uncommon to find lettuce falling out, and the topmost bun sliding. However, a good sandwich architect knows thatone must not rely on toothpicks or cardboard boxes for support, because those are removed. Make sure the sandwich is not top-heavy, and that the ingredients are arranged evenly, otherwise they may shift when picked up.