Consider the very foreseeable 'unforeseen consequences' of suggestions such as this. Think of all the views you may find undesirable. Now how many of them do you think could round up 3.5% of people to engage in disruptive behavior if they believed it would let them 'win'?

You end up in a situation where you want people you agree with to engage in disruptive behavior, but not people you disagree with. Yet messaging like this would fully motivate everybody. It seems likely to ultimately do little more than encourage fringe extremism because you have to remember everybody always seems themselves as the good guy. Let them think they can win with a negligible minority of disruption, and you're strongly motivating extreme behavior from fringe groups. For that matter you even motivate people who like to play puppeteer. Imagine you're a billionaire and you now believe you can achieve near anything you want if you can just get 3.5% of people to start misbehaving.

Getting your way by misbehavior is exactly what we aimed to move away from with democracy. And I completely agree with you on the failings of democracy which does seem to be trending towards idiocracy. At the same time, I think this is the sort of solution where the cure is far worse than the disease. You keep the same idiocracy, but now you convince them that they can get whatever they want if they start trying to break down normal civil order. And the current establishment in politics would use it, similar to 9/11, as an excuse to greatly expand domestic surveillance and further strip away privacy and various civil rights. You know, for 'your' protection.

With regard to "telling people about the 3.5% theory", I think that decision depends on how much you believe that "hopelessness" is playing a psychological part in our collective problems, or inability to deal with the largest threats.

I agree when it comes to "getting your way by misbehaviour", that democracy is designed to improve on that.

But if we generalise to "change caused by individuals' actions", which may not be the change each direct actioner demands, so much as the consequence of their applied lives, that covers more things.

For example, climate change activists who don't fly and tell others not to, are not causing a democratic catastrophe, yet they are having an effect and it's probably disproportionate and probably good.

I don't think that's chaos, I think it's a form of distributed intelligence and attention process. Albeit a messy one, without monotonic improvements.

I don't think the suggestions OP had were very extreme but even if they were civil disobedience is a very key part of democracy. The civil rights movement at the time was viewed by many as misbehavior and extremism. I think it changed our society for the better.