Dweller on the Threshold
Maybe they are. But someone who doesn’t understand Latin isn’t going to find it funny because they won’t know it’s nonsensical, and someone who does understand Latin is probably just going to find it irksome to see nonsensical strings of words (yet again), so I’m just going to have to admit I don’t get it. But there could be a portion of the Venn diagram I’m overlooking. At least in my case, it’s also a personal issue (related to my profession) and something I’m so weary of that I’m just not capable of finding it funny at the best of times.Welp, there's where we disagree.
1) The Merits are more or less in-universe goals of a mystery cult; they're traits and abilities the Fidelus explicitly tries to train its members in, like the Masques of the Guardians.
2) The founder is explicitly, as noted, uneducated and prone to accepting things at face value.
3) If the only example you can thing of is later in-universe admitted to be bad Latin, I think the writers may be way ahead of you and are poking fun at themselves.
But I don’t mean to rain on the parade of those who find it hilarious. Nor do I want to make an excellent and useful book out to be bad because of it; I was just answering a question someone asked in a way that expressed my feelings on the matter.