> But unfortunately these addresses are hard to remember and "nobody" recognizes them when reading examples.

How does that matter? The point isn't that the reader should know that "oh, this is a reserved address". The point is that there should be no room for the address that's actually being used by someone to end up being used incorrectly just because it showed up in some random documentation.

Much like how you probably wouldn't be thrilled if your phone number was used as an example in some random documentation somewhere.

For me it's the opposite: I usually misremember 192.0.0.0/8 as being entirely private, so for 192.0.2.0/32, I usually assume that the example given is supposed to be a private v4 address/network.

Anyone who writes technical documentation about networking knows the key ranges, and at least TEST-NET-1 (192.0.2/24) is pretty easy to remember. You only gotta look it up a few times, instead of being sloppy and justifying so with “no one cares anyway”.

It partly because attitudes like that is why software is a mess. Too few people care about correct semantics, everyone is satisfied with whatever sticks. From lists for sets, to tag soup instead of markup, and so on - all the way to modern code slop.

</rant>

> But unfortunately these addresses are hard to remember and "nobody" recognizes them when reading examples.

Mmm.

It's pretty easy to put three IPv4 /24s on a sticky note on your monitor. I think it's not unfair to say that if one can remember every fact related to one's job, then one has a job with a very, very small scope.

Also, this is another great reason to use IPv6. The v6 documentation prefix is '2001:db8::/32'... plenty of space for example subnets and easy to remember.