I forget where but someone proposed regularly rotating your DKIM key and publishing old keys for deniability. So you can still use strong keys and provide a level of deniability.
DKIM might have convinced the witness sometimes though.
It is the lawyers appearing before the court that may attempt to play the person not the ball, by variously undermining or bolstering their standing as an expert at all.
* an example supporting the counter-example is simply another counter-example, and
* an example contradicting the counter-example is, by definition, also another counter-example.
Corollary: all examples that can be opposed or contradicted by counter-examples are themselves also counter-examples.
I would argue it should be taught in schools.
It's a basic life skill, to be aware of what it means and how common it is. How do you function in society being oblivious of these facts? Basically by perennially becoming a victim to these, or by becoming bitter.
Just knowing about it is half the battle.
I would also add other dark personality types with potential to cause you real harm to the list - BPD and NPD.
School yourself, save yourself a whole lot of bad surprises. Over a lifetime being aware of the existence of these means you are on the lookout for warning signs, and you learn to get better at picking up on warning signs faster.
Sometimes you've just gotta love those auto-shortened URLs: security.googleblog.com/2013/12/internet-wide-efforts-to-fight-email.html
Hopefully one day we'll win the fight.
PS. Of course y'all young'uns won't remember ...