Reasoning by Lego happens when a designer or developer understands cryptography as Lego blocks stacked together. The blue block (the MAC) is sitting on top of the red block (the encryption), therefore the blue block won’t fall down. [..] The Lego view is not wrong. It’s an intuitive way to think of crypto algorithms when you’re writing the code. But it’s the wrong way to think about cryptographic security.

https://www.cryptofails.com/post/121201011592/reasoning-by-lego-the-wrong-way-to-think-about

Seems my TBR pile holds several gems... well, last one for today