[cricalix]

Physical letters do not obviate scams, nor is the cost that prohibitive. I remember actual 419 scams on blue airmail all-in-one letters back in the 80s. And that was international post too.

[AlecSchueler]

Think of it like changing your SSH port. It does nothing to prevent scams per se but you'll have to deal with only 0.00001% of them.

[skeeter2020]

If you build an analogy based on what I get in my mailbox it's more like publishing your email on the internet.

[riffraff]

They don't remove it but they do reduce it.

I have an inbox, and I do not receive a lot of scam post. In fact, I don't think I received any since I lived at this address (~10 years ). We do get a few promotional leaflets every other week.

OTOH, I get hundred of spam emails every day.

The former is something which I can handle manually easily, the other is not.

[tristramb]

It doesn't have to prevent the scam completely, it just has to make harder for them to scam you than it would be to move on to scam someone else.

[Freak_NL]

If you are targetting a list of well-known authors I guess outsourcing the writing of a couple of hundred handwritten letters shouldn't be too hard. I'm sure they they can find a school class in Nigeria or Kenya who would gladly do it for a few dollars — or a struggling teacher willing to get creative with the homework assignments.