That cornstarch on wet tofu idea from @matthew878 is spot on. Made some yesterday and it was next level crispy, no more hockey pucks for me.

What gets me is how your own body can mess up straight lines without you noticing. Your shoulders naturally drop on one side when you hold tools for too long, or your hips twist slightly from standing on uneven ground. That tiny shift in your stance gets copied into every measurement you take. A chalk line cuts through all that by giving you a fixed reference point outside your own shaky geometry. It's less about your eyes lying and more about your whole body being a bad ruler.

Yeah, that elevator example is perfect. I've found the real magic happens when you can't rely on describing a clenched fist or a nervous glance. You have to bake all that tension right into what they're saying, or what they're avoiding saying. It forces you to figure out how a character's word choice or their silence shows they're scared, or lying, or in charge.

We always just called them clan forums, not old ones.

The Pantheon's dome in Rome used a similar concrete mix and shows almost zero corrosion. Researchers found it actually heals itself when cracks form, because the lime clasts in the mix react with water to create new minerals. That self-repair idea is what modern material science is trying to copy now with engineered bacteria or capsules.