Small stones can start an avalanche, a single added uranium brick can put a pile over criticality.
While 'Project Pet Outsider' was called 'Project Pet Outsider', even the name of the project obviously-to-a-Chelish-person needed to be secret, since the fact that Cheliax had a pet outsider was explicitly secret.
A dath ilani would've never called it 'Project Lawful'. That means the name of the project is entangled with its contents in any way whatsoever! If the name needs to be readable at all, call it Project Artichoke or something else generated true-randomly. And then deploy single-use disposable pseudonyms whenever possible, if the person doesn't need to know *the* project name to enable a persistent conversational subject, which they usually don't.
From a Chelish standpoint? You can't figure out what Project Lawful is really doing from hearing that it's called Project Lawful. Why, it probably even gives Cheliax's enemies the wrong idea, if the name leaks somehow! Nobody's going to figure out the existence of Keltham or deduce a prospect of revolutionary military advances from *that*. So the name 'Project Lawful' is fine to tell to people who are not allowed to know what Project Lawful is about.
And let's face it, 'Project Lawful' is a really cool name. 'Lawful' is a powerful but standard concept that could potentially mean all sorts of specific things. Very evocative, while also very mysterious. Slightly ominous. You could say it's a tease.
As for whether it is in fact a good idea to assign a top-secret project a really cool name, well, that is something of a separate issue.