Probably ridiculous, really.
Were I planning some nefarious scheme which involved others the last thing I'd do is use any of those words in an electronic transmission.
My electronic communications would sound as innocent as a "Depends" ad, and would have a one time feature.
I think monitoring those words are a waste of time. No one up to no good is going to be broadcasting "en clair".
And maybe some are silly enough to do it. I don't know.