@knuckey:
Yes, it [blocking title creation based upon crownlaw_title = { has_law = no_title_creation } in the allow of the affected titles] is a rather simple solution. Blocking creation of titles of tier higher than current title tier based upon a crown law title is also extremely simple. Plus, you get properly explanatory tooltips in the title screen that actually reference which applied crown law title is blocking their creation (no small thing!) and such for free. The only cost is 1-2 lines of code in your relevant titles' allow clauses.
I imagine that it could be a little annoying if you're blocking it at the count level for ALL titles, admittedly, but wouldn't you rather Captain Gars spent his time making it possible to, say, join specific/exact war(s) by event (your suggestion last year, right?) or deal with various other total roadblocks in CK2 scripting instead of adding a minor convenience at a relatively high time cost? That said, if it's important to you that hard-code supports this pattern, then I suppose you should definitely add it back to the list (or I will).
I don't mean to tread on these suggestions. I do think that we need to do a certain degree of editing to emphasize game-changers for moddability over stuff that's already solved but neat, though. There is simply too much important stuff that is simply impossible to do correctly or at all, by any stretch of redundancy or inelegance.
EDIT:
That said, there's a lot of outright junk on the wiki (i.e., stuff that doesn't really make sense at all or is horribly specific such that Gars would never spend time adding it for an audience of one or now none), so the aforementioned suggestions do stand above those. I just don't have the heart to remove the stuff, though.
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