> although I imagine > they would be able to find a more efficient or less FP-risky way of writing > them.
Not necessarily. Other than the things I mentioned, I don't see anything particularly scarey about these rules. We have certainly written rules of this sort to catch other things. By preference we'd go for multiple rawbody rules and a meta. But there are things that you can't catch reliably that way, and this might be one of them. No telling if the rules are actually decent until the mass check results come out. You can have something that works really well for you, and it will hit absolutely nothing for anyone else, or it will FP all over the place. Usually in the later case you can see what went wrong and make a variation that will get around most or all the FPs, and sometimes you can widen a rule to hit more spam and not FP. Loren