Some folks consider themselves "rational persons." I think the phrase is an oxymoron; almost everyone makes most of their decisions emotionally and uses their reason to confabulate. I'm no less guilty--indeed, probably moreso--than the next person. However, I like to think that when I recognize patently irrational decisions (that is, those that tend to minimize expected value) based on emotional impulses, I am capable of bringing them under control.
Yesterday I received one of the pink slips in my mailbox that usually means I have an oversize package waiting at the post office. Today I went to pick it up, and instead of a package was handed a certified letter from the IRS. I was immediately nervous and curious as to why the IRS would be sending me certified mail, so I quickly signed for it and rushed out of the post office to open it in the parking lot. Turns out my tax payment for the 3rd quarter was late and they're adding a $10 penalty, and they certify the notification really just as a matter of policy. It's not as if they're really going to pay a lawyer to go to court to prove that I received this letter and owe them an additional $10.
This is the third or fourth time I've received certified mail in my life, and they've all been letters I'd rather not have received. After all, the only reason people send certified letters is that they want to prove, presumably in court, that you've received whatever it is they sent you, i.e. that you are aware of the contents of their letter and cannot reasonably claim otherwise. So the very fact of receiving a certified letter lets me know it contains something I might want to someday deny having knowledge of.
So why do I keep signing for them? When you get a certified letter, the smart thing to do is to put down the pen and walk away and let the post office or mail carrier keep it. The only reason people continue to sign is that they're frightened and curious and don't want to have to worry for two weeks about what was in the letter in the first place. But you're really doing your enemies a favor by signing, and if their beef is really important you'll find out about it eventually, whether you sign the letter or not. Smarter by far to not sign and see if they go away.