So what you're saying here is that we are both saying that decapitation strikes are a thing that works, the argument you wished was simply one of when they work.

Well I would point out that other people saw our discussion and took from it that "It does not work" was a valid conclusion from it, so the onus is not entirely on me. But yeah, sure, it is worth bearing in mind that decapitation strikes are much more likely to work when you have some sort of succession with legitimacy that is amenable to your goals. It is unlikely to do you much good if #2 hates you as much as #1 and wishes to follow the same plan.